Handbook of clinical drug data - part 10 doc

Elevated by abacavir P, acarbose P, acetaminophen I,P, acetohexamide P, acyclovir P, albendazoleP, alitretinoin P, allopurinol P, amiodarone P, ampicillin I, anabolicsteroids P, anastroz

ELECTROLYTES (mEq/L)

FOR GENERAL PURPOSE

OSMOLARITY BCAAs ESSENTIAL TOTAL N PO 4 OSMOLARITY

ELECTROLYTES (mEq/L)

FOR LIVER DISEASE

a Also available as Aminosyn II which contains glutamic and aspartic acids, and differs slightly in content of other amino acids, acetate, and chloride.

b Contains glycerol as a nonprotein calorie source.

c BCAA–enriched products Each of these products has distinct indications for use and should not be interchanged.

d Contains only BCAA Other essential AA are not included.

AA, amino acid; BCAA, branched-chain amino acid.

placement therapy such as peritoneal or hemodialysis require essential andnonessential AAs and should receive standard AA solutions.

Hepatic Failure Patients with hepatic failure, in whom muscle breakdown and

an altered serum and CNS AA profile might contribute to hepatic encephalopathy,can benefit from a special AA formula This formula has relatively greateramounts of BCAAs (ie, leucine, isoleucine, valine) and smaller amounts of thearomatic acids (ie, phenylalanine, tyrosine, tryptophan) and methionine.26Oneparenteral formula, HepatAmine, is currently available specifically for therapeutic

and nutrition support of patients with liver disease (see Table 6–8).

Stress and Trauma The hypermetabolism that occurs in response to stress andtrauma presents difficulty in providing nutrition support BCAAs, in addition totheir useful effect in metabolic support of the patient with liver disease, are re-ported to be useful for patients with stress and trauma.27,28Three BCAA-enriched

products are available (see Table 6–8) FreAmine HBC and Aminosyn HBC are

solutions of nonessential and essential AAs enriched with BCAAs BranchAmin4% is a solution of only BCAAs intended for use as a supplement to be admixedwith a complete AA and a nonprotein caloric source These products are indicatedonly for stress and trauma and should not be confused with the BCAA-enrichedproduct that is indicated for hepatic encephalopathy

Pediatrics It is beyond the scope of this chapter to describe procedures for trition support of pediatric patients except for this brief mention of parenteral AAproducts Crystalline AA solutions marketed for infants are based on the essential-

nu-ity of certain AAs in these patients (see Table 6–8).29Compared with adult AAformulations, these products contain taurine and glutamic and aspartic acids In-creased amounts of tyrosine and histidine and lower amounts of phenylalanine,methionine, and glycine are included Although cysteine is also assumed to be es-sential for infants, adequate amounts cannot be included in AA formulas because

of its limited solubility A cysteine solution (50 mg/mL) is available separately foradmixture to the formula before administration

■ ELECTROLYTES

Formulas also are available with standard electrolyte compositions that might besuitable for most patients, after the addition of certain additives Electrolyte provi-sion, however, should be based on close monitoring of patients’ laboratory values.Average daily requirements are summarized in Table 6–9

VITAMINS

Vitamin requirements for PN have been suggested in a report by an advisorygroup to the American Medical Association (AMA).30Multiple vitamins are avail-

able in adult and pediatric formulations for once-daily IV administration (see

Table 6–10) The usual daily dosage of the adult formulation is 10 mL to providethe amounts of vitamins specified in Table 6–10 The daily dosage of the pediatricformulation for infants who weigh <1 kg is 1.5 mL For infants weighing 1–3 kg,the daily dosage is 3 mL For infants and children weighing ≥3 kg up to 11 yr of

1042 NUTRITIONSUPPORT

AVERAGE DAILY

CATIONS

Sodium 60–150 mEq Sodium chloride concentrate (4 mEq/mL) Requirements during parenteral nutrition should not differ from

Sodium acetate (2 mEq/mL) normal fluid therapy requirements unless there is excessive Sodium phosphate (4 mEq Na+/mL) sodium loss Lactate and bicarbonate salts of sodium should not be used.

Potassium 40–240 mEq Potassium chloride (2 mEq/mL) Requirements are related to glucose metabolism and therefore

Potassium acetate (2 mEq/mL) increase with higher concentrations of dextrose infused.

Potassium phosphate (4.4 mEq K +/mL)Magnesium 10–45 mEq Magnesium sulfate (4 mEq/mL) Requirements increase with anabolism but with less variation than

with potassium.

Calcium 5–30 mEq Calcium gluconate 10% (4.5 mEq/10 mL) Requirements increase only slightly during parenteral nutrition.

Calcium chloride 10% (13 mEq/10 mL) Limited amounts of calcium and phosphate, as determined by compatibility

references, may be combined in solutions that contain amino acids.

ANIONS

Phosphate 10 mmol/1000 kcal Potassium phosphate (3 mmol P/mL, Abbott) Requirements increase with anabolism Safe empirical dosage

Sodium phosphate (3 mmol P/mL, Abbott) guidelines should be developed, taking into account the sodium (other concentrations may vary according or potassium content of the phosphate solution.

to manufacturer) Acetate and The amounts of acetate and chloride contained in each amino acid solution vary (See Table 6–8.) Acetate is metabolized to bicarbonate

age, the daily dosage is 5 mL Vitamin K is included in the pediatric product only.Phytonadione 5 mg may be given to adults weekly in the PN formula, or by IM or

SC administration, if needed.30

Fat emulsion contains vitamin K Intralipid 10% contains about 0.31 mg/Land Liposyn II contains 0.13 mg/L; 20% products contain twice as much In-tralipid 20% 500 mL provides about 300 g of vitamin K, an amount that exceedsmaintenance recommendations and interferes with oral anticoagulant therapy.30

1044 NUTRITIONSUPPORT

TABLE 6–10 IV MULTIVITAMINS

AMOUNT TYPICAL FORMULA Adult (per vial) Pediatric (5 mL)

PN has been described, there are no officially recommended requirements forthese elements.32–34

IRON

Iron deficiency can occur in patients deprived of iron during long-term PN Irondextran is sometimes added to PN solutions, but the advisability of its routine use

and its compatibility with fat emulsion are questionable Dosage tions by this route are 1–12.5 mg/day of iron.36

recommenda-INSULIN

Many patients who receive PN become hyperglycemic When feasible, the causeshould be investigated and controlled by means other than insulin before insulin is

employed (see Table 6–12) Although the efficacy of PN is reportedly enhanced by

insulin,37it should be used cautiously to avoid hypoglycemia and because it motes deposition of fatty acids in body fat stores, making them less available forimportant biochemical pathways.38When it is required, insulin may be providedseparately by SC or IV administration or added to the PN formula Until a patient isstabilized on a consistent dosage of insulin, it is more cost effective to provide in-sulin separately to avoid wasting of PN formulations that might be discarded if theinsulin dosage needs to be changed.39Human insulin is the least immunogenic and

pro-is therefore the insulin of choice Guidelines for dosage are empirical; one-half totwo-thirds of the previous day’s sliding scale requirements may be added as regularhuman insulin to the daily PN formula Standardized admixture procedures should

be used to minimize variations of insulin activity caused by adsorption loss

NUTRITIONSUPPORT 1045

TABLE 6–11 SUGGESTED DAILY IV DOSAGE OF TRACE ELEMENTS

ADULT IN STABLE ADULT PEDIATRIC ACUTE WITH TRACE PATIENTS CATABOLIC INTESTINAL ELEMENT ( µG/kg) a STABLE ADULT STATE b LOSSES b

Zinc 400 (preterm) c 2.5–4 mg Additional Add 12.2 mg/L of

250 (<3 months) d 2 mg small-bowel fluid

100 (>3 months–1 yr) d lost; 17.1 mg/kg of

50 (>1 yr) d stool or ileostomy

b Frequent monitoring of plasma levels in these patients is essential to provide proper dosage.

c Premature infants (weight <1500 g) up to 3 kg of body weight Thereafter, the recommendations for full-term infants apply.

d Full-term infants and children ≤5 yr old Thereafter, the recommendations for adults apply, up to a maximum dosage of 4 mg/day.

e Values derived by mathematical fitting of balance data from a 71 patient-week study in 24 patients.

f Mean from balance study.

Modified from references 31 and 35.

1046 NUTRITIONSUPPORT

TABLE 6–12 NUTRITION SUPPORT: METABOLIC COMPLICATIONS

AND MANAGEMENT

COMPLICATION FREQUENT CAUSES MANAGEMENT

Hyponatremia Excessive GI or urinary Increase sodium provision.

sodium losses, or inadequate sodium intake.

Excessive water intake Limit free water.

Hypokalemia Excessive GI or urinary potassium Increase potassium provision.

losses; deficit of potassium; or large glucose infusion.

Hypocalcemia Insufficient calcium Increase calcium provision.

Magnesium deficit Increase magnesium provision.

Hypomagnesemia Insufficient magnesium; or

excessive GI or urinary losses Increase magnesium provision.

Hypophosphatemia Inadequate phosphate Increase phosphate provision.

Refeeding syndrome Refeed gradually.

Hypoglycemia Abrupt interruption of formula Begin dextrose infusion and

moni-infusion tor blood glucose and potassium Excessive insulin Decrease insulin.

Hyperglycemia Deficit of potassium or Increase potassium or phosphate

phosphorus provision.

Insufficient insulin Give insulin.

Corticosteriod use Reduce rate of glucose infusion Sepsis Sepsis workup and treatment.

Hypertriglyceridemia Impaired clearance Hold IV lipid if serum triglycerides

>400 mg/dL (4.5 mmol/L).

Elevated BUN Dehydration Correct dehydration.

Renal dysfunction; or calorie: Increase nonprotein nitrogen ratio imbalance gen ratio.

calorie:nitro-Elevated Liver Underlying disease; lack of GI use; Attempt enteral feeding.

Function Tests or GI bacterial overgrowth.

Essential fatty acid deficiency Provide lipid.

Excessive nutrients Decrease PN.

Metabolic Acidosis Excessive GI or urinary losses Increase acetate provision.

of base.

Inadequate amount of base- Decrease chloride in formula or producing substance in formula crease acetate provision.

in-Osmotic Diuresis Failure to recognize initial Reduce infusion rate.

hyperglycemia and increased Give insulin to correct glucose in urine glycemia.

Albumin is compatible when admixed with PN formulas; however, its supply istoo limited and its cost is too prohibitive for casual use Although inclusion of al-bumin in PN is reported to rapidly increase serum albumin levels40and enhancetolerance of enteral feedings,41the clinical benefits of such treatment are notproved For synthesis of endogenous protein, albumin is inferior to crystallineAAs as a parenteral source of nitrogen If administration of albumin is necessary,

it should not be included in the PN formula

CARNITINE

Carnitine is a micronutrient that is vital to energy metabolism because of its role

in transporting long-chain fatty acids across the mitochondrial membrane Certainpatients, such as those with chronic renal failure on dialysis and prematureneonates, are at increased risk of developing carnitine deficiency, especially ifthey are receiving long-term PN.42,43 L-carnitine, the physiologically active form,

is available for IV administration as a 1 g/5 mL solution that is stable when added

to PN formulas.44Consult the carnitine product information for detailed usage formation

in-MEDICATIONS

There may be advantages to the admixture of certain medications such as otics, chemotherapeutic agents, and H2-receptor antagonists to PN, if there is com-patibility reported with all components of the formula Consult other sources forinformation regarding the stability and compatibility of medication/PN admix-tures

antibi-■ MONITORING THE PATIENT

Metabolic complications known to occur with enteral or parenteral nutrition aresummarized in Table 6–12 Most of these can be avoided by proper precautions

NUTRITIONSUPPORT 1047

TABLE 6–12 NUTRITION SUPPORT: METABOLIC COMPLICATIONS

AND MANAGEMENT (continued )

COMPLICATION FREQUENT CAUSES MANAGEMENT

Give 5% dextrose and 0.2% or 0.45% NaCl rather than PN solu- tion to correct dehydration Continue to monitor blood glucose, sodium, and potassium.

Essential Fatty Insufficient provision of Provide lipid.

Acid Deficiency fat during PN.

and close monitoring of the patient Laboratory parameters for patient monitoringare summarized in Table 6–13.

Vital signs, weight, intake, and output Daily.

Serum glucose, electrolytes, creatinine, Daily until stable, then twice weekly and BUN

Magnesium, calcium, and phosphorus Daily until stable, then once weekly CBC, hemoglobin, WBC, platelets, and Baseline, then weekly.

prothrombin time.

Serum protein, albumin, prealbumin, and Baseline, then weekly.

liver functions.

Serum cholesterol and triglycerides Baseline, then weekly.

Blood ammonia Baseline, then weekly in renal and hepatic

pro-Body composition research is presenting innovative approaches to metabolicand nutrition assessments.45Formulas with specialized AA mixtures continue to

be investigated The benefits of using BCAA-enriched formulas are reported forpatients with hepatic encephalopathy46or hypermetabolism47but remain unproved

in terms of morbidity and mortality Recombinant human growth factors,48nine,49and glutamine50offer promise for their beneficial influences on proteinsynthesis rates, immunocompetence, and intestinal mucosal barrier protection, re-spectively

argi-In vitro and animal studies report an improvement in tissue protein synthesisand reduction in hypermetabolic response with the enteral use of structured lipidscontaining MCTs and omega-3 fish oil.51,52Because of difficulties reported withthe IV use of currently available LCT emulsions such as hepatic and pulmonarycomplications and immunosuppression, alternate shorter-chain lipid preparationshave been investigated.53MCTs continue to be explored for IV use as an obligatefuel and an important component of PN.54Animal studies with short-chain triglyc-

erides such as triacetin show potential for better protein-sparing properties thanMCTs, with less toxicity.53Short-chain fatty acids also have been shown to bebeneficial in inhibiting small-bowel mucosal atrophy when infused IV or intra-colonically.55

New insights into the relationship between nutrition and immune functionare emerging through advances with recombinant monokines and new discoveriesconcerning the involvement of interleukin-1 and tumor necrosis factor in energymetabolism.52,56Although all of these are promising areas of research, they are notconsidered standard therapy in nutrition support

■ REFERENCES

1 Albina JE Nutrition and wound healing JPEN 1994;18:367–76.

2 Elwyn DH Nutritional requirements of adult surgical patients Crit Care Med 1980;8:9–19.

3 Grant JP et al Current techniques of nutritional assessment Surg Clin North Am 1981:61:437–63.

4 Blackburn GL et al Nutritional and metabolic assessment of the hospitalized patient JPEN 1977;1:11–22.

5 Traub SL, ed Basic skills in interpreting laboratory data Bethesda, MD: American Society of Hospital

8 Bistrian BR Recent advances in parenteral and enteral nutrition: a personal perspective JPEN 1990;14:329–34.

9 Liggett SB, Renfro AD Energy expenditures of mechanically ventilated nonsurgical patients Chest 1990;98:

682–6.

10 Rutten P et al Determination of optimal hyperalimentation infusion rate J Surg Res 1975;18:477–83.

11 Rees RGP et al Elemental diet administered nasogastrically without starter regimens to patients with

inflamma-tory bowel disease JPEN 1986;10:258–62.

12 Payne-James JJ, Khawaja HT First choice for total parenteral nutrition: the peripheral route JPEN 1993;17:

468–78.

13 Solomon SM, Kirby DF The refeeding syndrome: a review JPEN 1990;14:90–7.

14 Food and Drug Administration Safety alert: hazards of precipitation associated with parenteral nutrition Am J

Hosp Pharm 1994;51:1427–8.

15 Barton RG Nutrition support in critical illness Nutr Clin Pract 1994;9:127–39.

16 Shizgal HM, Forse RA Protein and calorie requirements with total parenteral nutrition Ann Surg 1980;

192:562–9.

17 Barr LH et al Essential fatty acid deficiency during total parenteral nutrition Ann Surg 1981;193:304–11.

18 Mattox TW, Teasley-Strausberg KM Overview of biochemical markers used for nutrition support DICP 1991;

25:265–71.

19 Roulet M et al Effects of intravenously infused egg phospholipids on lipid and lipoprotein metabolism in

post-operative trauma JPEN 1993;17:107–12.

20 Crowe PJ et al A new intravenous emulsion containing medium-chain triglyceride: studies of its metabolic

ef-fects in the perioperative period compared with a conventional long-chain triglyceride emulsion JPEN

1985;9:720–4.

21 Driscoll DF et al Practical considerations regarding the use of total nutrient admixtures Am J Hosp Pharm

1986;43:416–9.

22 Pineault M et al Beneficial effect of coinfusing a lipid emulsion on venous patency JPEN 1989;13:637–40.

23 Hardin TC Intravenous lipids—depression of the immune function: fact or fantasy? Hosp Pharm 1994;29:

182,185–6.

24 Guidelines for the use of parenteral and enteral nutrition in adult and pediatric patients American Society for

Parenteral and Enteral Nutrition JPEN 1993;17(4 suppl):1SA–52SA.

25 Humbestone DA et al Relative importance of amino acid infusion as a means of sparing protein in surgical

patients JPEN 1989;13:223–7.

26 Freund H et al Infusion of branched-chain enriched amino acid solution in patients with hepatic

encephalopa-thy Ann Surg 1982;196:209–20.

27 Freund H et al Infusion of the branched-chain amino acids in postoperative patients: anticatabolic properties.

NUTRITIONSUPPORT 1049

28 Cerra FB et al Branched-chains support postoperative protein synthesis Surgery 1982;92:192–9.

29 Heird WC et al Pediatric parenteral amino acid mixture in low birth weight infants Pediatrics 1988;81:41–50.

30 Baumgartner T, ed Clinical guide to parenteral nutrition 3rd ed Deerfield, IL: Fujisawa, Inc; 1997.

31 American Medical Association Department of Foods and Nutrition Guidelines for essential trace element

prepa-rations for parenteral use: a statement by an expert panel JAMA 1979;241:2051–4.

32 Lane HW et al The effect of selenium supplementation on selenium status of patients receiving chronic total

parenteral nutrition JPEN 1987;11:177–82.

33 Abumrad NN et al Amino acid intolerance during prolonged total parenteral nutrition reversed by molybdate

therapy Am J Clin Nutr 1981;34:2551–9.

34 Shils ME, Jacobs DH Plasma iodide levels and thyroid function studies in long term home TPN patients Am J

Clin Nutr 1983;37:731 Abstract.

35 Greene HL et al Guidelines for the use of vitamins, trace elements, calcium, magnesium, and phosphorus in fants and children receiving total parenteral nutrition: report of the Subcommittee on Pediatric Parenteral Nutri- ent Requirements from the Committee on Clinical Practice Issues of the American Society for Clinical Nutri-

in-tion Am J Clin Nutr 1988;48:1324–42.

36 Norton JA et al Iron supplementation of total parenteral nutrition: a prospective study JPEN 1983;7:457–61.

37 Shizgal HM, Posner B Insulin and the efficacy of total parenteral nutrition Am J Clin Nutr 1989;50:1355–63.

38 Rothkopf MM et al Nutritional support in respiratory failure Nutr Clin Pract 1989;4:166–72.

39 Sajbel TA et al Use of separate insulin infusions with total parenteral nutrition JPEN 1987;11:97–9.

40 Brown RO et al Response of serum albumin concentrations to albumin supplementation during central total

par-enteral nutrition Clin Pharm 1987;6:222–6.

41 Andrassy RJ, Durr ED Albumin: use in nutrition and support Nutr Clin Pract 1988;3:226–9.

42 Wolk R Micronutrition in dialysis Nutr Clin Pract 1993;8:267–76.

43 Bonner CM et al Effects of parenteral L-carnitine supplementation on fat metabolism and nutrition in premature

47 Teasley KM, Buss RL Do parenteral nutrition solutions with high concentrations of branched-chain amino acids

offer significant benefits to stressed patients? DICP 1989;23:411–6.

48 Hatton J et al Growth factors in nutritional support Pharmacotherapy 1993;13:17–27.

49 Daly JM et al Immune and metabolic effects of arginine in the surgical patient Ann Surg 1998;208:512–23.

50 Li J et al Glycyl-L-glutamine–enriched total parenteral nutrition maintains small intestine gut-associated

lym-phoid tissue and upper respiratory tract immunity JPEN 1998;22:31–6.

51 Teo TC et al Administration of structured lipid composed of MCT and fish oil reduces net protein catabolism in

enterally fed burned rats Ann Surg 1989;210:100–6.

52 Endres S The effect of dietary supplementation with n-3 polyunsaturated fatty acids on the synthesis of

inter-leukin-1 and tumor necrosis factor by mononuclear cells N Engl J Med 1989;320:265–71.

53 Bailey JW et al Triacetin: a potential parenteral nutrient JPEN 1991;15:32–6.

54 Mascioli EA et al Thermogenesis from intravenous medium-chain triglycerides JPEN 1991;15:27–31.

55 Koruda MJ et al Parenteral nutrition supplemented with short-chain fatty acids: effect on the small-bowel

mucosa in normal rats Am J Clin Nutr 1990;51:685–9.

56 Pomposelli JJ et al Role of biochemical mediators in clinical nutrition and surgical metabolism JPEN

1050 NUTRITIONSUPPORT

■ SI UNITS

SI units (le Système International d’Unités) are being introduced in the United

States to express clinical laboratory and serum drug concentration data Instead ofemploying units of mass (such as micrograms), the SI system uses moles (mol) torepresent the amount of a substance A molar solution contains 1 mole (the molec-ular weight of the substance in grams) of the solute in 1 liter of solution The fol-lowing formula is used to convert units of mass to moles (µg/mL to µmol/L or, bysubstitution of terms, mg/mL to mmol/L or ng/mL to nmol/L)

Micromoles per Liter ( mol/L)

Drug concentration (µg/mL) × 1000µmol/L = Molecular weight of drug (g/mol)

■ MILLIEQUIVALENTS

An equivalent weight of a substance is that weight which will combine with or place 1 g of hydrogen; a milliequivalent is 1/1000 of an equivalent weight

re-Milliequivalents per Liter (mEq/L)

Weight of salt (g) × Valence of ion × 1000mEq/L =

Molecular weight of saltmEq/L × Molecular weight of saltWeight of salt (g) =

Valence of ion × 1000

APPROXIMATE MILLIEQUIVALENTS—WEIGHTS OF SELECTED IONS

SALT mEq /g SALT mg SALT/mEq Calcium Carbonate (CaCO 3 ) 20.0 50.0 Calcium Chloride (CaCl 2  2H 2 O) 13.6 73.5 Calcium Gluceptate (Ca[C 7 H 13 O 8 ] 2 ) 4.1 245.2 Calcium Gluconate (Ca[C 6 H 11 O 7 ] 2  H 2 O) 4.5 224.1 Calcium Lactate (Ca[C 3 H 5 O 3 ] 2  5H 2 O) 6.5 154.1 Magnesium Gluconate (Mg[C 6 H 11 O 7 ] 2  H 2 O) 4.6 216.3 Magnesium Oxide (MgO) 49.6 20.2

(continued )

1053

■ ANION GAP

The anion gap is the concentration of plasma anions not routinely measured bylaboratory screening It is useful in the evaluation of acid–base disorders Theanion gap is greater with increased plasma concentrations of endogenous (eg,phosphate, sulfate, lactate, ketoacids) or exogenous (eg, salicylate, penicillin, eth-ylene glycol, ethanol, methanol) species The formulas for calculating the aniongap follow:

1054 APPENDICES

APPROXIMATE MILLIEQUIVALENTS—WEIGHTS OF SELECTED IONS (continued )

SALT mEq/g SALT mg SALT/mEq Magnesium Sulfate (MgSO 4 ) 16.6 60.2

Magnesium Sulfate (MgSO 4  7H 2 O) 8.1 123.2

Potassium Acetate (K[C 2 H 3 O 2 ]) 10.2 98.1

Potassium Chloride (KCl) 13.4 74.6

Potassium Citrate (K 3 [C 6 H 5 O 7 ]  H 2 O) 9.2 108.1

Potassium Iodide (KI ) 6.0 166.0

Sodium Acetate (Na[C 2 H 3 O 2 ]) 12.2 82.0

Sodium Acetate (Na[C 2 H 3 O 2 ]  3H 2 O) 7.3 136.1

Sodium Bicarbonate (NaHCO 3 ) 11.9 84.0

Sodium Chloride (NaCl ) 17.1 58.4

Sodium Citrate (Na 3 [C 6 H 5 O 7 ]  2H 2 O) 10.2 98.0

Sodium Iodide (NaI ) 6.7 149.9

Sodium Lactate (Na[C 3 H 5 O 3 ]) 8.9 112.1

Zinc Sulfate (ZnSO 4  7H 2 O) 7.0 143.8

VALENCES AND ATOMIC WEIGHTS OF SELECTED IONS

SUBSTANCE ELECTROLYTE VALENCE MOLECULAR WEIGHT Calcium Ca++ 2 40.1 Chloride Cl– 1 35.5 Magnesium Mg++ 2 24.3 Phosphate HPO=4 (80%) 1.8 96.0*

(pH = 7.4) H 2 PO−4 (20%)

Potassium K+ 1 39.1 Sodium Na+ 1 23.0 Sulfate SO=4 2 96.0*

*The molecular weight of phosphorus only is 31; that of sulfur only is 32.1.

(A) Anion Gap = (Na++ K+) − (Cl−+ HCO−3)

or

(B) Anion Gap = Na+− (Cl−+ HCO−3)where

the expected normal value for A is 11–20 mmol/L;

the expected normal value for B is 7–16 mmol/L.*

*Note that there is variation at the upper and lower limits of the normal range.

■ TEMPERATURE

Fahrenheit to Centigrade: (°F − 32) × 5/9 = °C

Centigrade to Fahrenheit: (°C × 9/5) + 32 = °F

Centigrade to Kelvin: °C + 273 = °K

■ WEIGHTS AND MEASURES

Metric Weight Equivalents

8 drams (D) = 1 ounce (O)

1 ounce (O) = 480 grains

12 ounces (O) = 1 pound (lb)

CONVERSIONFACTORS 1055

Apothecary Volume Equivalents

60 minims (M) = 1 fluidram (fl D)

8 fluidrams (fl D) = 1 fluid ounce (fl O)

1 fluid ounce (fl O) = 480 minims

16 fluid ounces (fl O) = 1 pint (pt)

Avoirdupois Equivalents

1 ounce (oz) = 437.5 grains

16 ounces (oz) = 1 pound (lb)

1 ounce (O) = 31.1 grams

1 ounce (oz) = 28.35 grams

1 mg = 1/65 gr

1056 APPENDICES

2

■ CREATININE CLEARANCE FORMULAS

FORMULAS FOR ESTIMATING CREATININE CLEARANCE

IN PATIENTS WITH STABLE RENAL FUNCTION

Adults [Age 18 Years and Older] 1

BSA = body surface area in m2

Clcr= creatinine clearance in mL/min

Crs= serum creatinine in mg/dL

Height is in cm

FORMULA FOR ESTIMATING CREATININE CLEARANCE

FROM A MEASURED URINE COLLECTION

U × V*

Clcr(mL/min) =

P × twhere

U = concentration of creatinine in a urine specimen (in same units as P)

V = volume of urine in mL

1057 Anthropometrics

P = concentration of creatinine in serum at the midpoint of the urine collectionperiod (in same units as U)

t = time of the urine collection period in minutes (eg, 6 hr = 360 min; 24 hr = 1440min)

*The product of U × V equals the production of creatinine during the collection period and, at steady state, should equal 20–25 mg/kg/day ideal body weight (IBW) in males and 15–20 mg/kg/day IBW in females If it is less than this, inadequate urine collection may have occurred and Cl cr will be under- estimated.

■ IDEAL BODY WEIGHT

IBW is the weight expected for a nonobese person of a given height The IBWformulas below and various life insurance tables can be used to estimate IBW.Most dosing methods described in the literature use IBW as a method in dosingobese patients

Adults [Age 18 years and Older] 3

IBW (Males) = 50 + (2.3 × Height in inches over 5 feet)IBW (Females) = 45.5 + (2.3 × Height in inches over 5 feet)where IBW is in kg

Children [Age 1–18 Years] 2

Under 5 Feet Tall:

(Height2× 1.65)IBW =

1000where

■ SURFACE AREA NOMOGRAMS

Nomograms represent the relationship between height, weight, and body surfacearea in infants and adults To use a nomogram, a ruler is aligned with the heightand weight on the two lateral axes The point at which the centerline is intersectedprovides the corresponding value for body surface area

1058 APPENDICES

NOMOGRAM FOR DETERMINATION OF BODY SURFACE AREAFROM HEIGHT AND WEIGHT (INFANTS)4

ANTHROPOMETRICS 1059

SA = W0.5378× H0.3964× 0.024265where

SA is in m2

Height (H) is in cm

Weight (W) is in kg

1060 APPENDICES

NOMOGRAM FOR DETERMINATION OF BODY SURFACE AREAFROM HEIGHT AND WEIGHT (ADULTS)5

SA = W0.425× H0.725× 71.84where

1 Cockcroft DW, Gault MH Prediction of creatinine clearance from serum creatinine Nephron 1976;16:31–41.

2 Traub SL, Johnson CE Comparison of methods of estimating creatinine clearance in children Am J Hosp Pharm

1980;37:195–201.

3 Devine BJ Gentamicin therapy Drug Intell Clin Pharm 1974;8:650–5.

4 Haycock GB et al Geometric method for measuring body surface area: a height–weight formula validated in

infants, children, and adults J Pediatr 1978;93:62–6.

3

The following table lists typical reference ranges for clinical laboratory tests incommon use Reference ranges for laboratory tests can vary widely among testingfacilities, often as a result of methodologic differences It is therefore always ad-visable to obtain reference ranges from the laboratory performing the analyses.Laboratory test results should never be accepted without correct identification ofthe units of measurement because most tests can be reported in several systems ofmeasurement The table presents conventional and international (usually the same

as Système International, or SI) units.

The following abbreviations are used to identify the specimen:

(P) — Plasma

(S) — Serum

(U) — Urine

(WB) — Whole Blood

(WB, art) — Whole Blood, Arterial

The table begins on page 1062

Blood, Serum, Plasma Chemistry; Urine, Renal Function Tests; Hematology

William G Troutman

1061 Laboratory Indices

BLOOD, SERUM, PLASMA CHEMISTRY

AGE GROUP OR REFERENCE RANGETEST/SPECIMEN OTHER FACTOR Conventional International Units

Acid Phosphatase (S) 0.11–0.60 units/L 0.11–0.60 units/L Alanine Aminotransferase (S) units/L units/L

(ALT, SGPT) Adult 8–20 8–20

>60 yr, M 7–24 7–24

>60 yr, F 7–16 7–16 Alkaline Phosphatase (S) units/L units/L

Child 20–150 20–150 Adult 20–70 20–70

>60 yr 30–75 30–75 Ammonia Nitrogen (S,P) Adult 15–45 mg/dL 11–32 µmol/L Amylase (S) units/L units/L

Adult 25–125 25–125

>70 yr 20–160 20–160 Anion Gap (Na + 2 [Cl−+ HCO − 3]) (P) 7–16 mEq/L 7–16 mmol/L

Aspartate Aminotransferase (S) units/L units/L

(AST, SGOT) Adult 8–20 8–20

>60 yr, M 11–26 11–26

>60 yr, F 10–20 10–20 Bicarbonate (S) mEq/L mmol/L

Arterial 21–28 21–28 Venous 22–29 22–29 (WB, art) Adult 18–23 18–23

Adult 8.4–10.2 2.10–2.55 Carbon Dioxide, Partial Pressure (WB, art) mm Hg kPa

(pCO 2 ) Adult, M 35–48 4.66–6.38

Adult, F 32–45 4.26–5.99 Chloride (S,P) 98–107 mEq/L 98–107 mmol/L

1062 APPENDICES

BLOOD, SERUM, PLASMA CHEMISTRY (continued )

AGE GROUP OR REFERENCE RANGETEST/SPECIMEN OTHER FACTOR Conventional International Units

Cholesterol, Total (S,P) mg/dL mmol/L

Child 120–200 3.11–5.18 Adolescent 120–210 3.11–5.44 Adult 140–310 3.63–8.03 Desired, Adult <200 <2.6 Cortisol (S,P) µg/dL nmol/L

08:00 hr 5–23 138–635 16:00 hr 3–15 83–414 20:00 hr ≤50% of 08:00 hr ≤50% of 08:00 hr Creatine Kinase (CK) (S) units/L units/L

Adult, M 38–174 38–174 Adult, F 26–140 26–140 Creatinine (S,P) mg/dL µmol/L

Child 0.3–0.7 27–62 Adolescent 0.5–1.0 44–88 Adult, M 0.7–1.3 62–115 Adult, F 0.6–1.1 53–97 ( )-Glutamyltransferase (S) units/L units/L

(GGT) Adult, M 9–50 9–50

Adult, F 8–40 8–40 Glucose, 2-hr Postprandial (S) <120 mg/dL <6.7 mmol/L Glucose Tolerance Test (S) mg/dL mmol/L

(Oral) Normal Diabetic Normal Diabetic

Fasting 70–105 140 3.9–5.8 7.8

60 min 120–170 200 6.7–9.4 ≥11.1

90 min 100–140 200 5.6–7.8 ≥11.1

120 min 70–120 140 3.9–6.7 ≥7.8 HDL-Cholesterol (S,P) mg/dL mmol/L

15–19 yr, M 30–65 0.78–1.68 15–19 yr, F 30–70 0.78–1.81 20–29 yr, M 30–70 0.78–1.81 20–29 yr, F 30–75 0.78–1.94 30–39 yr, M 30–70 0.78–1.81 30–39 yr, F 30–80 0.78–2.07

LABORATORYINDICES 1063

BLOOD, SERUM, PLASMA CHEMISTRY (continued )

AGE GROUP OR REFERENCE RANGETEST/SPECIMEN OTHER FACTOR Conventional International Units

>40 yr, M 30–70 0.78–1.81

>40 yr, F 30–85 0.78–2.20 Iron (S) µg/dL mmol/L

Child 50–120 8.95–21.48 Adult, M 65–170 11.64–30.43 Adult, F 50–170 8.95–30.43 Iron-Binding Capacity, Total (S) 250–450 µg/dL 44.75–80.55 µmol/L (TIBC)

Isocitrate Dehydrogenase (S) 1.2–7.0 units/L 1.2–7.0 units/L Lactate Dehydrogenase (S) units/L units/L

Child 60–170 60–170 Adult 100–190 100–190

>60 yr 110–210 110–210 Isozymes (S) % of Total Fraction of Total

Fraction 1 14–26 0.14–0.26 Fraction 2 29–39 0.29–0.39 Fraction 3 20–26 0.20–0.26 Fraction 4 8–16 0.08–0.16 Fraction 5 6–16 0.06–0.16 Lead (WB) µg/dL µmol/L

Child <15 <0.72 Adult <30 <1.45 Lipase (S) units/L units/L

Child, Adult 275–295 275–295

>60 yr 280–301 280–301

1064 APPENDICES

BLOOD, SERUM, PLASMA CHEMISTRY (continued )

AGE GROUP OR REFERENCE RANGETEST/SPECIMEN OTHER FACTOR Conventional International Units

Osmolal Gap ≤10 ≤10

Measured Osmolality − Calculated Osmolality

Calculated Osmolality = 2(Na+) + (Glucose/18) + (BUN/2.8)

Oxygen, Partial Pressure (WB, art) (pO 2 ) 83–108 mm Hg 11.04–14.36 kPa (Decreases with age and altitude)

pH (WB, art) 7.35–7.45 7.35–7.45 Phosphorus, Inorganic (S) mg/dL mmol/L

Child 4.5–5.5 1.45–1.78 Adult 2.7–4.5 0.87–1.45

>60 yr, M 2.3–3.7 0.74–1.20

>60 yr, F 2.8–4.1 0.90–1.32 Potassium (S,P) mEq/L mmol/L

Child 3.4–4.7 3.4–4.7 Adult 3.5–5.1 3.5–5.1 Protein, Total (S) g/dL g/L

Adult Ambulatory 6.4–8.3 64–83 Recumbent 6.0–7.8 60–78

>60 yr lower by 0.2 lower by 2 Albumin Adult 3.5–5.0 35–50

>60 yr 3.7–4.7 37–47 Globulins Adult 2.3–3.5 23–35 Prealbumin Adult 10–40 mg/dL 100–400 mg/L Sodium (S,P) mEq/L mmol/L

Child 138–145 138–145 Adult 136–146 136–146 Thyroid-Stimulating Hormone (S,P) µunits/mL munits/L

BLOOD, SERUM, PLASMA CHEMISTRY (continued )

AGE GROUP OR REFERENCE RANGETEST/SPECIMEN OTHER FACTOR Conventional International Units

Thyroxine, Total (S) µg/dL nmol/L

(T 4 ) 5–10 yr 6.4–13.3 83–172

Adult 5–12 65–155

>60 yr, M 5–10 65–129

>60 yr, F 5.5–10.5 71–135 4–9 mo pregnant 6.1–17.6 79–227 Transferrin (S) mg/dL g/L

Adult 220–400 2.20–4.00

>60 yr 180–380 1.80–3.80 Triglycerides (S) mg/dL mmol/L

12–15 yr 36–138 41–138 0.41–1.56 0.46–1.56 16–19 yr 40–163 40–128 0.45–1.84 0.45–1.45 20–29 yr 44–185 40–128 0.50–2.09 0.45–1.45 30–39 yr 49–284 38–160 0.55–3.21 0.43–1.81

` 40–49 yr 56–298 44–186 0.63–3.37 0.50–2.10

50–59 yr 62–288 55–247 0.70–3.25 0.62–2.79 Desired, Adult <150 <1.69 Triiodothyronine Resin Uptake (S) % of Total Fraction of Total

(T 3 RU) Adult 24–34 0.24–0.34

>60 yr, M 24–32 0.24–0.32

>60 yr, F 22–32 0.22–0.32 Triiodothyronine, Total (S) ng/dL nmol/L

(T 3 ) 10–15 yr 80–210 1.23–3.23

Adult 120–195 1.85–3.00

>60 yr, M 105–175 1.62–2.69

>60 yr, F 108–205 1.66–3.16 Urea Nitrogen (S) mg/dL mmol/L urea

(BUN) Child 5–18 0.8–3.0

Adult 7–18 1.2–3.0

>60 yr 8–21 1.3–3.5 Uric Acid (S) mg/dL mmol/L

(Uricase Method) Child 2.0–5.5 0.12–0.32

Adult, M 3.5–7.2 0.21–0.42

1066 APPENDICES

LABORATORYINDICES 1067

URINE, RENAL FUNCTION TESTS

AGE GROUP OR REFERENCE RANGETEST/SPECIMEN OTHER FACTOR Conventional International Units

Catecholamines, 24-hr (U) <110 µg <650 nmol Creatinine, 24-hr (U) mg/kg µmol/kg

Child 8–22 71–195 Adolescent 8–30 71–265 Adult, M 14–26 124–230 Adult, F 11–20 97–177 Decreases with age to 10 mg/kg/day at age 90.

Creatinine Clearance (S, P, and U) mL/min/1.73 m 2 mL/sec/m 2

<40 yr, M 97–137 0.93–1.32

<40 yr, F 88–128 0.85–1.23 Decreases with age >40 yr.

Inulin Clearance (S and U) mL/min/1.73 m 2 mL/sec/m 2

20–29 yr 90–174 84–156 0.87–1.68 0.81–1.50 30–39 yr 88–168 82–150 0.85–1.62 0.79–1.44 40–49 yr 78–162 82–146 0.75–1.56 0.79–1.41 50–59 yr 68–152 66–142 0.65–1.46 0.63–1.37 60–69 yr 57–137 58–130 0.55–1.32 0.56–1.25 70–79 yr 42–122 45–121 0.40–1.17 0.43–1.17 80–89 yr 39–105 39–105 0.38–1.01 0.38–1.01

pH (U) 4.5–8 4.5–8

Protein, Total (U) 1–14 mg/dL 10–140 mg/L

At Rest 50–80 mg/day 50–80 mg/day Specific Gravity, Random (U) 1.002–1.030 1.002–1.030

Mean Corpuscular Volume 80–96 µm 3 80–96 fL Mean Corpuscular Hemoglobin 27–31 pg 27–31 pg Erythrocyte Sedimentation Rate (WB) mm/hr mm/hr

M 1–13 1–13

F 1–20 1–20 Fibrinogen (P) 200–400 mg/dL 2.00–4.00 g/L Hematocrit (WB) % Packed RBC Volume Volume Fraction

6–12 yr 35–45 0.35–0.45 12–18 yr, M 37–49 0.37–0.49 12–18 yr, F 36–46 0.36–0.46 18–49 yr, M 41–53 0.41–0.53 18–49 yr, F 36–46 0.36–0.46 Hemoglobin (WB) g/dL mmol/L

6–12 yr 11.5–15.5 1.78–2.40 12–18 yr, M 13.0–16.0 2.02–2.48 12–18 yr, F 12.0–16.0 1.86–2.48 18–49 yr, M 13.5–17.5 2.09–2.71 18–49 yr, F 12.0–16.0 1.86–2.48 Hemoglobin A 1c (WB) 5.3–7.5% of total Hb 0.053–0.075 Leukocyte Count (WB) 4.5–11 × 10 3 / L 4.5–11 × 10 9 /L

Segs 31–71% 31–71% Bands 0–12% 0–12%

Lymphocytes 15–50% 15–50% Monocytes 0–12% 0–12%

Eosinophils 0–5% 0–5%

Basophils 0–2% 0–2%

1068 APPENDICES

HEMATOLOGY (continued )

AGE GROUP OR REFERENCE RANGETEST/SPECIMEN OTHER FACTOR Conventional International Units

Absolute Neutrophil Count (ANC)

ANC = (% Segs + % Bands) × Leukocyte Count

Partial Thromboplastin Time, 25–37 sec 25–37 sec Activated (WB) (aPTT)

Platelets (WB) 150–440 × 10 3 / L 0.15–0.44 × 10 12 /L Prothrombin Time (WB) Less than 2-sec deviation from control Reticulocytes (WB) 0.5–1.5% 0.005–0.015

of erythrocytes

REFERENCES

1 Burtis CA, Ashwood ER, eds Tietz textbook of clinical chemistry 2nd ed Philadelphia: WB Saunders; 1994.

2 Henry JB, ed Clinical diagnosis and management by laboratory methods 18th ed Philadelphia: WB Saunders;

5 Tietz NW, ed Clinical guide to laboratory tests 2nd ed Philadelphia: WB Saunders; 1990.

6 Wallach J Interpretation of diagnostic tests: a synopsis of laboratory medicine 6th ed Boston: Little, Brown;

1996.

LABORATORYINDICES 1069

David G Dunlop

The following table lists common clinical laboratory tests and drugs that can fere with those tests Drugs can interfere with laboratory tests through pharmaco-logical or toxic effects or through actual chemical interference with the testingprocess Either effect can lead to an altered value of the laboratory test, resulting

inter-in an inter-inappropriate diagnosis or treatment It is therefore essential that clinter-iniciansrecognize possible drug–laboratory interactions and use this information in theoverall assessment of a patient’s clinical status

The table lists drug interferences with the most common laboratory tests Fordetailed information on laboratory tests not covered here, see references 1–3 at theend of this section Also, it should be noted that drugs can interfere with labora-tory tests by many different mechanisms The reader should refer to the referencescited in the table and other relevant sources to obtain more information about aspecific test

The following abbreviations are used in the table:

(B) — Blood

(CSF) — Cerebrospinal Fluid

(I) — Analytical Interference of Drug

(P) — Pharmacological/Toxic Effect of Drug

(S) — Serum

■ DRUGS THAT CAN AFFECT RESULTS AND CAUSE OF INTERFERENCE

BLOOD, SERUM, PLASMA CHEMISTRY

Alkaline Phosphatase (S) Elevated by acetaminophen (P), acetohexamide (P),

al-bumin (I), alitretinoin (P), allopurinol (P), aluminum salts (P), aminoglycosides(P), amiodarone (P), amphotericin B (P), anabolic steroids (P), azathioprine (P),barbiturates (P), bromocriptine (P), carbamazepine (P), cephalosporins (P), cheno-diol (P), clofibrate (P), cyclophosphamide (P), cyclosporine (P), cytarabine (P),danazol (P), dantrolene (P), dapsone (P), disulfiram (P), docetaxel (P), eryth-romycin (P), estrogens (P), filgrastim (P), flucytosine (P), glycopyrrolate (P), goldsalts (P), griseofulvin (P), haloperidol (P), hepatotoxic drugs (P), HMG-CoA re-ductase inhibitors (P), hydralazine (P), ibuprofen (I,P), isoniazid (P), isotretinoin(P), ketoconazole (P), lithium salts (P), meprobamate (P), mercaptopurine (P),

1070

Drug–Laboratory Test

methyldopa (P), mitomycin (P), nafarelin (P), niacin (P), nitrofurantoin (P), steroidal anti-inflammatory drugs (P), papaverine (P), penicillamine (P), peni-cillins (P), phenazopyridine (P), phenothiazines (P), phenytoin (P), pindolol (I),probenecid (P), propylthiouracil (P), pyrazinamide (P), quinidine (P), rifampin(P), sulfonamides (P), sulfonylureas (P), tetracyclines (P), thiabendazole (P), ticlo-pidine (P), topotecan (P), trimethoprim (P), troleandomycin (P), valproic acid (P),zidovudine (P).1,3,4

non-Decreased by bisphosphonates (P), calcitriol (P), carvedilol (P), citrate salts

(I), clofibrate (P), cyclosporine (P), danazol (P), EDTA (I), estrogens (P), fluoridesalts (I), phosphate salts (I), prednisolone (P), prednisone (P), tamoxifen (P), the-ophylline (I), tricyclic antidepressants (P), ursodiol (P), zinc (I).1,3

Aminotransferases (ALT [SGOT] or AST [SGPT]) (S) Elevated by abacavir (P),

acarbose (P), acetaminophen (I,P), acetohexamide (P), acyclovir (P), albendazole(P), alitretinoin (P), allopurinol (P), amiodarone (P), ampicillin (I), anabolicsteroids (P), anastrozole (P), asparaginase (P), azathioprine (P), aztreonam (P),barbiturates (P), carbamazepine (P), cephalosporins (P), chenodiol (P), chloral hy-drate (P), chloramphenicol (P), chlordiazepoxide (I,P), cholestyramine (P), cholin-ergic agents (P), clopidogrel (P), COX-2 inhibitors (P), cyclophosphamide (P), cy-tarabine (P), danazol (P), dantrolene (P), delavirdine (P), denileukin diftitox (P),disulfiram (P), diuretics (thiazide) (P), docetaxel (P), efavirenz (P), erythromycin(I,P), estrogens (P), etoposide (P), fenofibrate (P), fluconazole (P), flucytosine (P),flutamide (P), fomepizole (P), ganciclovir (P), gemcitabine (P), gemtuzamabozogamicin (P), gentamicin (I,P), glycopyrrolate (P), gold salts (P), griseofulvin(P), haloperidol (P), heparin (P), hepatotoxic drugs (P), HMG-CoA reductase in-hibitors (P), hydralazine (P), IM injections (P), indinavir (P), interferon alfa-2a(P), interferon beta-1a (P), interferon beta-1b (P), irinotecan (P), isoniazid (P), iso-proterenol (I), isotretinoin (P), ketoconazole (P), leflunomide (P), levodopa (I,P),meprobamate (P), mercaptopurine (P), methotrexate (P), methyldopa (I), mirtaza-pine (P), nafarelin (P), naltrexone (P), narcotics (I,P), nevirapine (P), niacin (P),nilutamide (P), nitrofurantoin (P), nonsteroidal anti-inflammatory drugs (P), olan-zapine (P), penicillamine (P), penicillins (I,P), pentosan polysulfate sodium (P),phenazopyridine (P), phenothiazines (P), porfimer (P), probenecid (P), propyl-thiouracil (P), pyrazinamide (P), quetiapine (P), quinidine (P), quinupristin/dalfo-pristin (P), rifabutin (P), rifampin (P), rifapentine (P), riluzole (P), ritonavir (P),salicylates (I,P), sulfonamides (P), sulfonylureas (P), tacrine (P), temozolomide(P), tetracyclines (P), thiabendazole (P), ticlopidine (P), tolcapone (P), topotecan(P), total parenteral nutrition (P), troleandomycin (P), valproic acid (P), vidarabine(P), vinorelbine (P), vitamin C, zafirlukast (P), zalcitabine (P), zidovudine (P).1–4,6

Decreased by acetaminophen (I), aspirin (I), cyclosporine (P), fluoride salts

(I), interferons (P), metronidazole (I), naltrexone (P), pindolol (I), rifampin (I), cyclic antidepressants (P), ursodiol (P), vitamin C (I), zalcitabine (P).1

tri-Ammonia (B) Elevated by acetazolamide (P), alcohol (P), ammonium chloride

(P), asparaginase (P), barbiturates (P), carbamazepine (P), diuretics (loop, azide) (P), isoniazid (P), parenteral nutrition (P), smoking (P), valproic acid.1,2,4,7

thi-DRUG–LABORATORYTESTINTERFERENCES 1071

Decreased by cefotaxime (I), kanamycin, oral (P), Lactobacillus acidophilus

(P), lactulose (P), MAO inhibitors (P), neomycin, oral (P), phosphate salts (I),potassium salts (P), tetracycline (P).1,2,4

Amylase (S) Elevated by alcohol (P), angiotensin II receptor blockers (P), ACE

inhibitors (P), asparaginase (P), azathioprine (P), chloride salts (I), cholinergicagents (P), cisplatin (P), contraceptives, oral (P), corticosteroids (P), denileukindiftitox (P), didanosine (P), diuretics, loop and thiazide (P), erythromycin (P), es-trogens (P), fluoride salts (I), indinavir (P), lamivudine (P), metronidazole (P),narcotics (P), nitrofurantoin (P), opioids (P), pancreatotoxins (P), potassium io-dide (P), rifampin (P), ritonavir (P), sulfonamides (P), valproic acid (P), vinorel-bine (P), zalcitabine (P).1,3,5,7

Decreased by anabolic steroids (P), cefotaxime (I), citrate salts (P), fluoride

salts (I), somatostatin (P).1

Bilirubin, Total (S) Elevated by acarbose (P), acetaminophen (P), acetohexamide

(P), allopurinol (P), amiodarone (P), amphotericin B (I,P), anabolic steroids (P),asparaginase (P), azathioprine (P), barbiturates (P), capecitabine (P), carba-mazepine (P), cephalosporins (P), chloramphenicol (P), cholinergics (P),colchicine (P), cyclophosphamide (P), cyclosporine (P), cytarabine (P), danazol(P), dantrolene (P), dapsone (P), dextran (I), disulfiram (P), diuretics, thiazide andloop (P), docetaxel (P), epinephrine (I), erythromycin (P), estrogens (P), etoposide(P), flutamide (P), gemtuzamab ozogamicin (P), glycopyrrolate (P), gold salts (P),haloperidol (P), hemolytic agents (P), hepatotoxic drugs (P), HMG-CoA reductaseinhibitors (P), hydralazine (P), indinavir (P), interferon beta-1b (P), irinotecan (P),isoniazid (P), isoproterenol (I), isotretinoin (P), ketoconazole (P), levodopa (I),meprobamate (P), mercaptopurine (P), methimazole (P), methotrexate (I,P),methyldopa (I,P), narcotics (I), niacin (P), nitrofurantoin (I,P), nonsteroidal anti-inflammatory drugs (P), papaverine (P), penicillamine (P), penicillins (P),phenazopyridine (I), phenothiazines (P), phenelzine (I), probenecid (P), propran-olol (I), propylthiouracil (P), pyrazinamide (P), quinidine (P), quinupristin/dalfo-pristin (P), rifampin (I,P), rifapentine (P), riluzole (P), salicylates (I,P), sulfon-amides (P), sulfonylureas (P), theophylline (I), thiabendazole (P), topotecan (P),troleandomycin (P), valproic acid (P), vitamin C (I), zafirlukast (P), zidovudine(P).1–3,5

Decreased by amikacin (I), barbiturates (especially in newborns) (P),

carba-mazepine (P), corticosteroids (P), cyclosporine (P), fexofenadine (P), isotretinoin(P), levodopa (I), nitrofurantoin (I), phenazopyridine (I), phenytoin (P), pindolol(I), sulfonamides (P), temozolomide (P), theophylline (I), ursodiol (P), vitamin C(I).3,4

Calcium (S) Elevated by alitretinoin (P), amifostine (P), anabolic steroids (P),

an-drogens (P), basiliximab (P), calcitriol (P), calcium salts (P), cefotaxime (I), propamide (I), diuretics, thiazide (P), estrogens (P), hydralazine (I), interferons(I), iron salts (I), lithium salts (P), magnesium salts (I), phenobarbital (P), pro-gestins (P), sevelamer (P), tamoxifen (P), toremifene (P), thyroid (P), vitamin A(P), vitamin D (P).1–5,7

chlor-1072 APPENDICES

Decreased by acetazolamide (P), albuterol (P), asparaginase (P), aspirin (I),

bisphosphonates (P), calcitonin (P), carbamazepine (P), cisplatin (P), citrate salts(P), contraceptives, oral (P), corticosteroids (P), diuretics, loop (P), EDTA (I),ethanol (P), fluoride salts (I,P), foscarnet (P), glucagon (P), heparin (I), laxatives(P), magnesium salts (P), phenobarbital (P), phenytoin (P), phosphate salts (P), pli-camycin (P), sodium polystyrene sulfonate (P), sulfisoxazole (I), zalcitabine (P).1–5

Carbon Dioxide (B) Elevated by bicarbonate salts (P), diuretics (loop, thiazide)

(P), respiratory depressants (P).1,3

Decreased by acetazolamide (P), aspirin overdose (P), nephrotoxic drugs

(P), theophylline (P).1,3

Chloride (S) Elevated by acetazolamide (P), anabolic steroids (P), aspirin (I,P),

carbamazepine (I), cefotaxime (I), cholestyramine (P), corticosteroids (by salt tention) (P), COX-2 inhibitors (P), cyclosporine (P), diuretics, carbonic anhydraseinhibitor, thiazide—chronically by alkalosis (P), estrogens (P), guanethidine (P),halogens (eg, bromides, fluorides) (I), methyldopa (P), nonsteroidal anti-inflammatory drugs (P), sodium phenylbutyrate (P).1,3

re-Decreased by allopurinol (I), bicarbonates (P), cefotaxime (metabolite) (I),

chlorpropamide (P), corticosteroids (by alkalosis) (P), diuretics, loop, thiazide—

by acute diuresis (P), fluoride salts (I), laxatives, long-term use (P), mannitol (P),mineralocorticoids (by alkalosis) (P), trimethoprim (P).1,3

Cholesterol, Total (S) Elevated by acetohexamide (P), -adrenergic blockingagents (P), alitretinoin (P), amiodarone (P), amphotericin B (I), amprenavir (P),anabolic steroids (by cholestasis) (P), aspirin (I), basiliximab (P), carbamazepine(P), cefotaxime (I), chenodiol (P), clopidogrel (P), contraceptives, oral (P), corti-costeroids (I,P), cyclosporine (P), danazol (P), dextran (I), diclofenac (P), disulfi-ram (P), diuretics, loop, thiazide (P), ethanol (P), fibrates (P), gold salts (P), hepa-totoxic drugs (cholestatic effect) (P), ibuprofen (P), imipramine (P), isotretinoin(P), meprobamate (P), methotrexate (I), mirtazapine (P), mycophenolate (P), naf-arelin (P), phenobarbital (P), phenothiazines (I,P), phenytoin (I,P), protease in-hibitors (P), quetiapine (P), ritonavir (P), rosiglitazone (P), sirolimus (P), smoking(P), sorbitol (P), sotalol (P), spironolactone (P), sulfadiazine (P), tamoxifen (P),tetracycline (I), thiabendazole (P), ticlopidine (P), vitamin A (I), vitamin C (I,P),vitamin D (I,P).1–5

Decreased by acarbose (P), acebutolol (P), α-adrenergic blockers (P), purinol (I,P), aluminum salts (P), amiloride (P), amiodarone (P), ampicillin (I), ana-bolic steroids (by inhibiting synthesis) (P), ACE inhibitors (P), asparaginase (P),azathioprine (P), calcium channel blockers (P), carvedilol (P), chlorpropamide(P), cholestyramine (P), citrate salts (I), clofibrate (P), clomiphene (P), colchicine(P), colestipol (P), diuretics, thiazide (P), estrogens (P), fenofibrate (P), fluoridesalts (I), haloperidol (P), hepatotoxic drugs (decreased synthesis) (P), HMG-CoA reductase inhibitors (P), hydroxychloroquine (P), insulin (P), isoniazid (P),isotretinoin (P), kanamycin, oral (P), ketoconazole (P), levothyroxine (P), MAOIs(P), metformin (P), methyldopa (I,P), metronidazole (P), neomycin, oral (P),niacin (P), nitrates (I), orlistat (P), penicillamine (I), pentamidine (P), phenytoin(P), pindolol (P), psyllium (P), raloxifene (P), rifampin (I), sevelamer (P) tamox-

allo-DRUG–LABORATORYTESTINTERFERENCES 1073

ifen (P), tetracyclines (P), thyroid (P), ursodiol (P), valproic acid (P), vitamin C(I,P).1–5

Coombs’ [Direct] (S) Positive by aztreonam (P), captopril (P), cephalosporins (P),

chlorpromazine (P), chlorpropamide (P), ethosuximide (P), hemolytic agents (P),hydralazine (P), imipenem/cilastatin (P), indomethacin (P), isoniazid (P), levo-dopa (P), mefenamic acid (P), melphalan (P), methyldopa (P), nitrofurantoin (P),penicillamine (P), penicillins (P), phenytoin (P), procainamide (P), quinidine (P),quinine (P), rifampin (P), sulfasalazine (P), sulfonamides (P), sulfonylureas (P), tetracyclines (P), tolmetin (I).1,3,4,6

Creatine Kinase (S) Elevated by alcohol (chronic) (P), aminocaproic acid (P),

amphotericin B (P), barbiturates (P), cefotaxime (I), clofibrate (P), cyclosporine(P), danazol (P), fenofibrate (P), HMG-CoA reductase inhibitors (P), gemfibrozil(P), IM injections (P), lithium salts (P), niacin (P), succimer (I), saquinavir (P), zi-dovudine (P).1,2,4,5

Decreased by amikacin (I), anesthetic agents (P), ascorbic acid (I), aspirin

(I), dantrolene (P), phenothiazines (P), pindolol (I), succinylcholine (P), famethoxazole (P), zalcitabine (P).1

sul-Creatinine (S) Elevated by acebutolol (P), acetaminophen (I,P), acetohexamide

(I), acyclovir (P), amiloride (P), aminoglycosides (P), amiodarone (P), tericin B (P), ACE inhibitors (P), antacids (P), asparaginase (P), aztreonam (P),carvedilol (P), cephalosporins (Jaffe method) (I,P), chloroquine (P), cidofovir (P),cimetidine (P), cisplatin (P), clofibrate (P), colistin (P), co-trimoxazole (P), cy-closporine (P), demeclocycline (P), denileukin diftitox (P), dextran (P), diuretics(P), dopamine (I), doxycycline (P), flucytosine (I,P), foscarnet (P), furosemide (I),ganciclovir (P), hydroxychloroquine (P), lactulose (I), levodopa (I), lidocaine (I),lithium (I,P), methicillin (P), methyldopa (I), mitomycin (P), nalidixic acid (P),nephrotoxic drugs (P), nifedipine (P), nitrofurantoin (I), nonsteroidal anti-inflammatory drugs (P), penicillamine (P), penicillin (I), pentamidine (P), phos-phate salts (P), radiocontrast agents (P), ritonavir (P), salicylates (P), sirolimus(P), sulbactam (I), sulfamethoxazole (I), tacrolimus (P), tetracycline (P), vanco-mycin (P), vitamin C (I), vitamin D (P).1–4,7

ampho-Decreased by amikacin (I), cephalosporins (I), citrate salts (I), dopamine (I),

ibuprofen (P), interferon alfa-2a (P), methyldopa (I), sulfonylureas (P), vitamin

C (I).1,5

Glucose (S) Elevated by abacavir (P), acetaminophen (SMA 12/60 method) (I),

ac-etazolamide (P), -adrenergic blocking agents (also mask hypoglycemia) (P), buterol (P), amiodarone (P), antidepressants (heterocyclic) (P), asparaginase (P),basiliximab (P), bicalutamide (P), cefotaxime (I), cholestyramine (P), citrate salts (I),clonidine (P), clozapine (P), corticosteroids (P), cyclosporine (P), daclizumab (P),dextran (I), dextroamphetamine (P), diazoxide (P), diclofenac (I), diltiazem (P), di-uretics, loop and thiazide (P), epinephrine (I,P), ephedrine (P), estrogens (P), fos-phenytoin (P), gemfibrozil (P), glucagon (P), interferon alfa-2a (P), iron dextran (I),isoniazid (P), isoproterenol (I), labetalol (I), lactose (I), levodopa (SMA 12/60

al-1074 APPENDICES

method) (I), lipids (P), lithium salts (P), mercaptopurine (I), methyldopa (I), nidazole (I), mycophenolate (P), nalidixic acid (I), niacin (I,P), nifedipine (P), oc-treotide (P), olanzapine (P), pentamidine (IV, paradoxical effect) (P), perphenazine(P), phenothiazines (P), phenytoin (P), pravastatin (P), progestins (P), propranolol(P), propylthiouracil (I), protease inhibitors (P), reserpine (P), rifampin (I,P), salicyl-ates (acute toxicity) (I,P), somatostatin (P), sorbitol (P), tacrolimus (P), terbutaline(P), tetracyclines (P), thiabendazole (P), thyroid (P), tolbutamide (P), vitamin C(neocuproin method) (I), zalcitabine (P).1–5

metro-Decreased by acarbose (P), acetaminophen (GOD-Perid method) (I,P),

ac-etazolamide (P), -adrenergic blocking agents (nonselective) (P), alcohol (P), lopurinol (P), amikacin (I), anabolic steroids (P), antihistamines (P), chloroquine(P), chlorpropamide (I,P), cimetidine (P), clofibrate (P), disopyramide (P), doxa-zosin (P), erythromycin (P), estrogens (P), gemfibrozil (P), interferon beta-1b (P),hydralazine (I), insulin (P), isoniazid (I), levodopa (glucose oxidase and othermethods) (I), lipids (I), MAO inhibitors (P), metformin (P), methyldopa (I),metronidazole (I), miglitol (P), niacin (P), octreotide (P), pentamidine (IV) (P),phenazopyridine (I), phosphorus (P), psyllium (P), repaglinide (P), salicylates(acute and chronic toxicity) (P), saquinavir (P), SSRIs (P), sulfonamides (P), sul-fonylureas (P), tetracyclines (I), thiabendazole (P), tolazolmide (I), tolbutamide(I,P), verapamil (P), vitamin C (GOD-Perid method) (I,P).1–3,6

al-Iron (S) Elevated by cefotaxime (I), chloramphenicol (P), cisplatin (P),

contracep-tives (oral) (P), estrogens (P), ferrous salts (I), iron, parenteral (I,P), methyldopa(P), miglitol (P), rifampin (I).1,3,5

Decreased by allopurinol (P), aspirin (large doses) (P), cholestyramine (P),

colchicine (P), deferoxamine (I,P), entacapone (P), metformin (P), penicillamine(P), pyrazinamide (I,P).1,3,5

Iron Binding Capacity, Total (S) Elevated by contraceptives, oral (P),

propyl-thiouracil (P).1,3,5

Decreased by chloramphenicol (P), corticotropin (P), corticosteroids (P).1,3,5

Magnesium (S) Elevated by cefotaxime (I), diuretics, potassium-sparing (P),

lithium salts (P), magnesium salts (P), pentamidine (P).1,3,4,6

Decreased by albuterol (P), alcohol (P), amifostine (P), aminoglycosides

(P), amphotericin B (P), bisphosphonates (P), calcium salts (I), cefotaxime (I), platin (P), citrate salts (I), contraceptive, oral (P), cyclosporine (P), digitalis (toxicconcentrations) (P), diuretics, loop, and thiazide (P), foscarnet (P), glucagon (P),insulin (P), tacrolimus (P).1,3,4,6

cis-Osmolality (S) Elevated by alcohol (ADH suppression) (P), citrate salts (I),

corti-costeroids (P), demeclocycline (ADH inhibition) (P), glucose (I), lithium salts(ADH inhibition) (P), mannitol (I,P).1,4

Decreased by antidepressants, tricyclic (P), carbamazepine (P),

chlorpro-pamide (P), clonidine (P), cyclophosphamide (P), cytarabine (P), diuretics, azide (P), haloperidol (P), interferon alfa (I), MAOIs (P), phenothiazines (P),SSRIs (P), sulfonylureas (P), vasopressin (P), vinca alkaloids (P).1,4

thi-DRUG–LABORATORYTESTINTERFERENCES 1075

Phosphate (S) Elevated by anabolic steroids (P), basiliximab (P), cefotaxime (I),

contraceptives, oral (P), foscarnet (P), mannitol (I), methicillin (I,P), pindolol (P),rifampin (I,P), sodium phenylbutyrate (P), vitamin D (excessive) (P).1,4

Decreased by acetazolamide (P), antacids (phosphate binding; eg,

alu-minum, calcium, and magnesium salts) (P), bisphosphonates (P), calcitonin (P),carbamazepine (P), cidofovir (P), citrate salts (I), foscarnet (P), insulin (P), lith-ium salts (P), mannitol (I), mycophenolate (P), parenteral nutrition (P), phenobar-bital (P), phenothiazines (P), phenytoin (P), sevelamer (P), sirolimus (P), sorbitol(P), sucralfate (P), tacrolimus (P).1,4–6

Potassium (S) Elevated by aminocaproic acid (P), angiotensin II receptor

block-ers (P), ACE inhibitors (P), β-adrenergic blockers (P), antineoplastic agents toxic effect) (P), basiliximab (P), cefotaxime (I), cisplatin (I), cyclosporine (P),COX-2 inhibitors (P), diuretics, potassium-sparing (P), fluconazole (P), fluoridesalts (I), heparins (P), iodide salts (I), isoniazid (P), lithium salts (P), low-molecular-weight heparins (P), mannitol (P), mycophenolate (P), nephrotoxicdrugs (P), nonsteroidal anti-inflammatory drugs (primarily indomethacin) (P),pentamidine (P), potassium penicillin (P), procainamide (I), salt substitutes (P),succinylcholine (P), tacrolimus (P), trimethoprim (P), tromethamine (P).1–6

(cyto-Decreased by acetazolamide (P), β-adrenergic agonists (P), aminoglycosides(P), ammonium chloride (P), amphotericin B (P), basiliximab (P), bicarbonatesalts (P), bisphosphonates (P), cisplatin (P), corticosteroids (P), diuretics (loop,thiazide) (P), fenoldopam (P), foscarnet (P), glucose (P), insulin (P), laxatives (P),levodopa (P), mineralocorticoids (P), mycophenolate (P), ondansetron (P), peni-cillins (extended-spectrum) (P), phosphate salts (P), salicylates (P), sirolimus (P),sorbitol (P), sodium polystyrene sulfonate (P), sodium phenylbutyrate (P), sul-fasalazine (P), tacrolimus (P).1–6

Protein, Total Elevated by anabolic steroids {S} (P), aspirin {CSF} (I),

cepha-lothin {S} (I), chloramphenicol {S} (I), corticosteroids {S} (P), dextran {CSF/S}(I), imipramine {CSF} (I), lidocaine {CSF} (I), mannitol {CSF} (I), methotrexate{CSF} (I), penicillins {S/CSF} (I), phenazopyridine {S} (I), phenothiazines{CSF} (I), progestins {S} (I), radiocontrast agents {S} (I), rifampin {S} (I), sul-fonamides {CSF} (I), tetracyclines {CSF} (I), thyroid {S} (P), vancomycin{CSF} (I), vitamin C {CSF} (I).1–3

Decreased by acetaminophen {CSF} (I), cefotaxime {CSF} (I),

contracep-tives, oral (from estrogen) {S} (P), cytarabine {CSF} (P/I), dexamethasone {CSF}(P), dextran {S} (I,P), estrogens {S} (P), hepatotoxic drugs {S} (P), pyrazinamide{S} (P), rifampin {S} (P).1–3

Sodium (S) Elevated by anabolic steroids (P), bicarbonate salts (P),

carba-mazepine (I,P), cefotaxime (I), cisplatin (I), clonidine (P), contraceptives, oral (P),corticosteroids (P), COX-2 inhibitors (P), diazoxide (P), estrogens (P), fluoridesalts (I), lactulose (P), mannitol (P), methyldopa (P), mineralocorticoids (P), nitro-furantoin (P), nonsteroidal anti-inflammatory drugs (P), sodium phenylbutyrate(P), tetracycline (P).1,3,5

Decreased by acetazolamide (P), ammonium chloride (P), amphotericin B

(P), antidepressants, tricyclic (P), bicarbonate salts (I), carbamazepine (P),

chlor-1076 APPENDICES

propamide (P), cisplatin (P), clonidine (P), cyclophosphamide (P), cytarabine (P),diuretics, loop and thiazide (P), haloperidol (P), indomethacin (P), interferons (P),laxatives (P), lithium salts (P), mannitol (P), MAOIs inhibitors (P), miconazole(P), nifedipine (P), nonsteroidal anti-inflammatory drugs (P), phenothiazines (P),SSRIs (P), somatostatin (P), spironolactone (P), sulfonylureas (P), vasopressinand analogues (P), trimethoprim (P), vinca alkaloids (P).1,3–5,7

Thyroxine (S) Elevated by amiodarone (I,P), clofibrate (P), contraceptives, oral

(from estrogen) (P), estrogens (P), fluorouracil (P), heparin (I), insulin (P), dopa (P), prazosin (P), propranolol (P), propylthiouracil (P), prostaglandins (P),radiocontrast agents (I,P), tamoxifen (P).1–6

levo-Decreased by anabolic steroids (P), asparaginase (P), barbiturates (P),

carba-mazepine (P), chlorpropamide (P), cholestyramine (P), clofibrate (P), colestipol(P), corticosteroids (P), danazol (I,P), diazepam (P), heparin (I), interferon alfa-2a(P), iodide salts (P), iron salts (P), lithium salts (P), penicillamine (P), phenytoin(P), propylthiouracil (P), reserpine (P), salicylates (P), sulfonamides (P), sulfonyl-ureas (P), thyroid (P).1–5

Triglycerides (S) Elevated by -adrenergic blockers (P), alitretinoin (P), darone (P), amprenavir (P), aspirin (I,P), cholestyramine (P), colestipol (P), con-traceptives, oral (P), cyclosporine (P), danazol (P), didanosine (P), diuretics, loopand thiazide (P), estrogens (P), fomepizole (P), interferon alfa-2a (P), isotretinoin(P), itraconazole (P), lipids (P), low-molecular-weight heparins (P), HMG-CoAreductase inhibitors (P), mirtazapine (P), nitroglycerin (I), olanzapine (P), pro-tease inhibitors (P), quinidine (P), ritonavir (P), sirolimus (P), tamoxifen (P).2–5

amio-Decreased by acarbose (P), α-adrenergic blockers (P), amiodarone (P), ACEinhibitors (P), asparaginase (P), aspirin (I), chenodiol (P), citrate salts (I), clofi-brate (P), danazol (P), fenofibrate (P), gemfibrozil (P), HMG-CoA reductase in-hibitors (P), hydroxychloroquine (P), hydroxyurea (I), ketoconazole (P), met-formin (P), methotrexate (I), methyldopa (I), naproxen (I), niacin (P), nifedipine(P), orlistat (P), probucol (P), psyllium (P), rifampin (I), spironolactone (P), sul-fonylureas (P), verapamil (P), vitamin C (I,P).1–4

Urea Nitrogen (S) Elevated by ACE inhibitors (P), acetazolamide (P),

acetohexa-mide (I), aminoglycosides (P), anabolic steroids (P), antacids (prolonged use) (P),asparaginase (P), busulfan (P), carbamazepine (P), chloral hydrate (I), chloram-phenicol (Nesslerization method) (I), cisplatin (P), clonidine (P), colistin (P), co-trimoxazole (P), cyclosporine (P), dexamethasone (P), dextran (I,P), diuretics,loop and thiazide (P), flucytosine (P), gold salts (P), hydralazine (P), hydroxyurea(P), ifosfamide (P), iron salts (P), methotrexate (P), methyldopa (P), methysergide(P), mitomycin (P), nalidixic acid (P), nephrotoxic drugs (P), nitrofurantoin (P),nonsteroidal anti-inflammatory drugs (P), penicillamine (P), pentamidine (P), ra-diocontrast agents (P), salicylates (P), sulfonamides (I), tacrolimus (P), tetracy-clines (I,P), vancomycin (P), vitamin D (P).1,3–5

Decreased by amikacin (I), ascorbic acid (I), cefotaxime (I),

chlorampheni-col (Berthelot method) (I), fluoride salts (I), levodopa (P), phenothiazines (P),streptomycin (I).1,3–5

DRUG–LABORATORYTESTINTERFERENCES 1077

Uric Acid (S) Elevated by acetaminophen (I), acetazolamide (P), anabolic steroids

(P), antineoplastics (P), azathioprine (P), basiliximab (P), caffeine (Bittnermethod) (I), cisplatin (P), citrate salts (P), cyclosporine (P), cytarabine (P), diaz-oxide (P), diuretics (carbonic anhydrase inhibitor, loop, thiazide) (P), epinephrine(I), ethambutol (P), filgrastim (P), hydralazine (I), isoniazid (I), levodopa (I,P),mercaptopurine (P), methyldopa (I), niacin (P), phenytoin (P), pyrazinamide (P),propranolol (P), propylthiouracil (P), rifampin (I), ritonavir (P), salicylates (lowdoses) (I,P), sodium phenylbutyrate (P), spironolactone (P), tacrolimus (P), theo-phylline (I,P), triamterene (P), vitamin C (I), zalcitabine (P).2–5

Decreased by acetohexamide (P), allopurinol (P), cefotaxime (I), cidofovir

(P), clofibrate (P), corticosteroids (P), diflunisal (P), fenofibrate (P), glucose sions (P), griseofulvin (P), guaifenesin (P), hydralazine (I), indomethacin (P),levodopa (I), lithium (P), losartan (P), mannitol (P), methyldopa (I), nonsteroidalanti-inflammatory drugs (P), phenothiazines (P), radiocontrast agents (P), salicyl-ates (large doses) (P), spironolactone (P), sulfonamides (P), uricosurics (eg,probenecid, sulfinpyrazone) (P), verapamil (P), vitamin C (by Seralyzer) (I,P).2–5

infu-URINE TESTS

Bilirubin Elevated by acetohexamide (P), etodolac (I), hepatotoxic drugs (P),

mefenamic acid (I), phenazopyridine (I), phenothiazines (I,P).1,5

Catecholamines Elevated by acetaminophen (I), α1-adrenergic blockers (P), hol (P), aspirin (I), atenolol (P), caffeine (P), chloral hydrate (I), chlorpromazine(I), dopamine (I,P), epinephrine (I), erythromycin (I), hydralazine (I), insulin (P),isoproterenol (I), labetalol (I), levodopa (I), methenamine (I), methyldopa (I),niacin (I), nifedipine (P), nitroglycerin (P), prochlorperazine (P), quinidine (I), re-serpine (P), tetracyclines (I,P), triamterene (P).1,2,4,5

alco-Decreased by α2-adrenergic blockers (P), bromocriptine (P), clonidine (P),disulfiram (P), guanethidine (P), methenamine (destroys catecholamines in blad-der urine) (P), radiocontrast agents (I), reserpine (P).1,2,4

Color (See Drug-Induced Discoloration of Feces and Urine, page 1024.) Creatinine Elevated by anabolic steroid (increased muscle mass) (P), aspara-

ginase (I), cephalosporins, except cefotaxime and ceftazidime; (Jaffe method) (I),corticosteroids (P), levodopa (I), methotrexate (P), methyldopa (I), nephrotoxicdrugs (P), nitrofurantoin (I), reserpine (P), vitamin C (I).1,4,5

Decreased by anabolic steroids (anabolic effect) (P), captopril (P),

cimeti-dine (P), diuretics, thiazide (P).1,4,5

Glucose Elevated or False Positive by aspirin (copper reduction) (I,P),

aminosali-cylic acid (copper reduction) (I), cephalosporins, except cefotaxime (copper duction) (I), chloral hydrate (copper reduction) (I), cidofovir (P), corticosteroids(P), dextroamphetamine (P), diuretics, loop and thiazide (P), glucagon (P), isoni-azid (P), levodopa (copper reduction) (I), lithium salts (P), nalidixic acid (I),niacin (P), penicillins (I), pentamidine (P), phenazopyridine (Tes-Tape) (I), phe-nothiazines (P), probenecid (I), reserpine (P), sulfonamides (I), vitamin C (copperreduction).1–6

re-1078 APPENDICES

Decreased or False Negative by aspirin (glucose oxidase) (I,P), bisacodyl

(I), chloral hydrate (glucose oxidase) (I), diazepam (I), digoxin (I), ferrous salts(I), flurazepam (I), furosemide (I), insulin (P), levodopa (glucose oxidase) (I),phenazopyridine (glucose oxidase) (I), phenobarbital (P), prednisone (glucose oxi-dase) (I), secobarbital (I), tetracycline (I), vitamin C (glucose oxidase).1–6

Gonadotropins (Pregnancy Test) False Positive by methadone (I),

phenoth-iazines (I).1,5

Ketones. Elevated by acetylcysteine (I), albuterol (P), captopril (I),cephalosporins (I), dimercaprol (I), insulin (P), isoniazid (P), levodopa (Labstix)(I), mesna (I), metformin (I), methyldopa (I), niacin (P), penicillamine (I),phenazopyridine (I), phenothiazines (I), pyrazinamide (I), salicylates (acidotic ef-fect) (I,P), succimer (I), valproic acid (I).1,2,4,5

Decreased by aspirin (oxidation of ketone bodies) (P), phenazopyridine (I).1

Protein Elevated by acetaminophen (P), acetazolamide (I), aminoglycosides (I,P),

asparaginase (P), bacitracin (P), bicarbonate salts (I), captopril (P), carbamazepine(P), cephalosporins (I,P), chlorpromazine (I), cidofovir (P), cisplatin (P), cy-closporine (P), delavirdine (P), dihydrotachysterol (I,P), diuretics, thiazide (P),gemcitabine (P), gold salts (P), griseofulvin (P), hydralazine (P), interferon beta-1b (P), iron salts (P), isoniazid (P), lithium salts (P), nephrotoxic drugs (P), non-steroidal anti-inflammatory drugs (P), penicillamine (P), penicillins (I), pentami-dine (P), phenazopyridine (I), radiographic agents (I), rifapentine (P), salicylates(I), sulfonamides (I), tetracycline (P), tolbutamide (I), vancomycin (P), vitamin C(I).1,5

Decreased by ACE inhibitors (P), cyclosporine (P), diltiazem (P), interferon

alfa-2a (P), prednisolone (P).1

Specific Gravity Elevated by dextran (P), diuretics (P), isotretinoin (P), mannitol

(P), radiographic agents (P), sucrose (P).1,4,5

Decreased by colistin (P), lithium (P).1

HEMATOLOGY

Erythrocyte Sedimentation Rate (B) Elevated by contraceptives, oral (P),

cy-closporine (P), dextran (P), isotretinoin (P), methyldopa (P), methysergide (P), trofurantoin (P), procainamide (P), theophylline (P), vitamin A (P).1,5

ni-Decreased by corticosteroids (P), cyclophosphamide (P), infliximab (P),

flu-oride salts (I), gold salts (P), methotrexate (P), nonsteroidal anti-inflammatorydrugs (P), penicillamine (P), quinine (P), salicylates (P), sulfasalazine (P), tamox-ifen (P), trimethoprim (P), drugs that cause hyperglycemia (P).1,5

Prothrombin Time (B) [Does not include anticoagulants or drugs which

potenti-ate or antagonize them] Elevpotenti-ated by acetaminophen (P), antibiotics (gut

steriliz-ing) (P), asparaginase (P), cephalosporins (P), chloramphenicol (P), chloral drate (P), chlorpromazine (P), chlorpropamide (P), cholestyramine (P), colestipol(P), cyclophosphamide (P), hepatotoxic drugs (P), laxatives (P), mercaptopurine

hy-DRUG–LABORATORYTESTINTERFERENCES 1079