Urine Drug Screening: Practical Guide for Clinicians
2008; Elsevier BV; Volume: 83; Issue: 1 Linguagem: Inglês
10.4065/83.1.66
ISSN1942-5546
AutoresKaren E. Moeller, Kelly C. Lee, Julie C. Kissack,
Tópico(s)Neurotransmitter Receptor Influence on Behavior
ResumoDrug testing, commonly used in health care, workplace, and criminal settings, has become widespread during the past decade. Urine drug screens have been the most common method for analysis because of ease of sampling. The simplicity of use and access to rapid results have increased demand for and use of immunoassays; however, these assays are not perfect. False-positive results of immunoassays can lead to serious medical or social consequences if results are not confirmed by secondary analysis, such as gas chromatography-mass spectrometry. The Department of Health and Human Services' guidelines for the workplace require testing for the following 5 substances: amphetamines, cannabinoids, cocaine, opiates, and phencyclidine. This article discusses potential false-positive results and false-negative results that occur with immunoassays of these substances and with alcohol, benzodiazepines, and tricyclic antidepressants. Other pitfalls, such as adulteration, substitution, and dilution of urine samples, are discussed. Pragmatic concepts summarized in this article should minimize the potential risks of misinterpreting urine drug screens. Drug testing, commonly used in health care, workplace, and criminal settings, has become widespread during the past decade. Urine drug screens have been the most common method for analysis because of ease of sampling. The simplicity of use and access to rapid results have increased demand for and use of immunoassays; however, these assays are not perfect. False-positive results of immunoassays can lead to serious medical or social consequences if results are not confirmed by secondary analysis, such as gas chromatography-mass spectrometry. The Department of Health and Human Services' guidelines for the workplace require testing for the following 5 substances: amphetamines, cannabinoids, cocaine, opiates, and phencyclidine. This article discusses potential false-positive results and false-negative results that occur with immunoassays of these substances and with alcohol, benzodiazepines, and tricyclic antidepressants. Other pitfalls, such as adulteration, substitution, and dilution of urine samples, are discussed. Pragmatic concepts summarized in this article should minimize the potential risks of misinterpreting urine drug screens. Drug testing beyond the health care and criminal justice systems has increased throughout the past decade. Common areas for drug testing include the workplace (eg, preemployment and random testing), the military, athletics, legal and criminal situations (eg, postaccident testing, rehabilitation testing of ex-convicts), and health care (eg, treatment, compliance monitoring, cause of death). Misinter-pretation of drug tests can have serious consequences, such as unjust termination from a job, risk of prison sentence, inappropriate exclusion from a sporting event, and possibly inappropriate medical treatment in emergencies. Our goal is to provide clinically relevant information that can be used to interpret urine drug screens (UDSs) for commonly abused drugs (ie, alcohol, amphetamines, benzodiazepines, opioids, marijuana, cocaine, phencyclidine [PCP], and tricyclic antidepressants [TCAs]). Proper evaluation of urine specimens, including detection times, are discussed, as well as false-positive results and potential false-negative results. Interpretation of tests for performance-enhancing drugs is beyond the scope of this article and is not discussed. Urine, blood, hair, saliva, sweat, and nails (toenails and fingernails) are some biological specimens used to perform laboratory drug testing, and they provide different levels of specificity, sensitivity, and accuracy. Urine is most often the preferred test substance because of ease of collection. Concentrations of drugs and metabolites also tend to be high in the urine, allowing longer detection times than concentrations in the serum allow.1Tests for drugs of abuse.Med Lett Drugs Ther. 2002; 44: 71-73PubMed Google Scholar Two types of UDSs are typically used, immunoassay and gas chromatography-mass spectrometry (GC-MS). Immunoassays, which use antibodies to detect the presence of specific drugs or metabolites, are the most common method for the initial screening process. Advantages of immunoassays include large-scale screening through automation and rapid detection.2Armbruster DA Schwarzhoff RH Hubster EC Liserio MK Enzyme immunoassay, kinetic microparticle immunoassay, radioimmunoassay, and fluorescence polarization immunoassay compared for drugs-of-abuse screening.Clin Chem. 1993; 39: 2137-2146PubMed Google Scholar Forms of immunoassay techniques include cloned enzyme donor immunoassay; enzyme-multiplied immunoassay technique (EMIT), a form of enzyme immunoassay; fluorescence polarization immunoassay (FPIA); immunoturbidimetric assay; and radioimmunoassay (RIA). In addition, immunoassay techniques are used in many home-testing kits or point-of-care screenings. The main disadvantage of immunoassays is obtaining false-positive results when detection of a drug in the same class requires a second test for confirmation. Results of immunoassays are always considered presumptive until confirmed by a laboratory-based test for the specific drug (eg, GC-MS or high-performance liquid chromatography). Yet even GC-MS can fail to identify a positive specimen (eg, hydromorphone, fentanyl) if the column is designed to detect only certain substances (eg, morphine, codeine).3Fenton JJ Toxicology: A Case-Oriented Approach. CRC Press, Boca Raton, FL2002: 359-402Google Scholar Gas chromatography-mass spectrometry is considered the criterion standard for confirmatory testing. The method is able to detect small quantities of a substance and confirm the presence of a specific drug (eg, morphine in an opiate screen). It is the most accurate, sensitive, and reliable method of testing; however, the test is time-consuming, requires a high level of expertise to perform, and is costly. For these reasons, GC-MS is usually performed only after a positive result is obtained from immunoassay. In postmortem analyses, lactate dehydrogenase and lactate were found to interfere with assays for commonly abused substances (amphetamine, barbiturates, benzodiazepines, opiates, and propoxyphene).4Sloop G Hall M Simmons GT Robinson CA False-positive postmortem EMIT drugs-of-abuse assay due to lactate dehydrogenase and lactate in urine.J Anal Toxicol. 1995; 19: 554-556Crossref PubMed Scopus (15) Google Scholar Additional confirmatory testing is advised for patients who have illnesses that increase the risk of lactic acidosis, such as diabetes mellitus, liver disease, and toxin ingestion (eg, ethanol, methanol, salicylates). The Department of Health and Human Services (DHHS) has established specific cutoff levels that define a positive result for the workplace (Table 15US Department of Health and Human Services Mandatory guidelines and proposed revisions to mandatory guidelines for federal workplace drug testing programs: notices.Federal Register. April 13, 2004; 69 (Accessed Novmeber 30, 2007.): 19659-19660http://ncadistore.samhsa.gov/catalog/ProductDetails.aspx?ProductID=16833Google Scholar). These values were developed to help eliminate false-positive results (eg, poppy seeds causing positive opium results). Values below the cutoff levels are reported as negative, which can lead to false-negative results. These values from the DHHS were established for the workplace only, and the role of these threshold levels in clinical settings (eg, health care, substance abuse programs) remains controversial because of the potential for false-negative results. Cutoff levels were developed for adults, and values might need to be lowered for children because their urine is more dilute than that of adults.6Luzzi VI Saunders AN Koenig JW et al.Analytic performance of immunoassays for drugs of abuse below established cutoff values.Clin Chem. 2004 Apr; 50 (Epub 2004 Feb 5.): 717-722Crossref PubMed Scopus (40) Google Scholar All laboratories should evaluate cutoff values for their specific patient populations.TABLE 1Federal Workplace Cutoff ValuesaGC-MS = gas chromatography–mass spectrometry.Data from reference 5US Department of Health and Human Services Mandatory guidelines and proposed revisions to mandatory guidelines for federal workplace drug testing programs: notices.Federal Register. April 13, 2004; 69 (Accessed Novmeber 30, 2007.): 19659-19660http://ncadistore.samhsa.gov/catalog/ProductDetails.aspx?ProductID=16833Google Scholar.SubstanceInitial drug test level (immunoassay) (ng/mL)Confirmatory drug test level (GC-MS) (ng/mL)Marijuana metabolitesbDelta-9-tetrahydrocannabinol-9-carboxylic acid.5015Cocaine metabolitescBenzoylecgonine.300150Opiate metabolites20002000Phencyclidine2525Amphetamines1000500MethamphetaminedSpecimen must also contain amphetamine at a concentration greater than or equal to 200 ng/mL.Incomplete data500a GC-MS = gas chromatography–mass spectrometry.b Delta-9-tetrahydrocannabinol-9-carboxylic acid.c Benzoylecgonine.d Specimen must also contain amphetamine at a concentration greater than or equal to 200 ng/mL. Open table in a new tab Several factors need to be considered to determine the length of time a drug or substance can be detected in the urine. Pharmacokinetics, presence of metabolites, patient variability (eg, body mass), short-term vs long-term use of a drug, pH of the urine, and time of last ingestion are some factors that influence detection times. Table 27Inaba DS Cohen WE Uppers, Downers, All Arounders: Physical and Mental Effects of Psychoactive Drugs. 5th ed. CNS Publications, Inc, Ashland, OR2004Google Scholar, 8Woelfel JA Drug abuse urine tests: false-positive results.Pharmacist Lett/Prescribers Lett. 2005; 21: 210-314Google Scholar, 9Council on Scientific Affairs Scientific issues in drug testing.JAMA. 1987; 257: 3110-3114Crossref PubMed Scopus (59) Google Scholar, 10Heit HA Gourlay DL Urine drug testing in pain medicine.J Pain Symptom Manage. 2004; 27: 260-267Abstract Full Text Full Text PDF PubMed Scopus (146) Google Scholar, 11Rosse RB Deutsch LH Deutsch SI Medical assessment and laboratory testing in psychiatry.in: Sadock BJ Sadock VA 7th ed. Kaplan and Sadock's Comprehensive Textbook of Psychiatry. Vol 1. Lippincott, Williams & Wilkins, Philadelphia, PA2000: 732-755Google Scholar, 12Verstraete AG Detection times of drugs of abuse in blood, urine, and oral fluid.Ther Drug Monit. 2004; 26: 200-205Crossref PubMed Scopus (349) Google Scholar reports usual detection times for drugs of abuse discussed in this article.TABLE 2Length of Time Drugs of Abuse Can Be Detected in UrineData from references 7Inaba DS Cohen WE Uppers, Downers, All Arounders: Physical and Mental Effects of Psychoactive Drugs. 5th ed. CNS Publications, Inc, Ashland, OR2004Google Scholar, 8Woelfel JA Drug abuse urine tests: false-positive results.Pharmacist Lett/Prescribers Lett. 2005; 21: 210-314Google Scholar, 9Council on Scientific Affairs Scientific issues in drug testing.JAMA. 1987; 257: 3110-3114Crossref PubMed Scopus (59) Google Scholar, 10Heit HA Gourlay DL Urine drug testing in pain medicine.J Pain Symptom Manage. 2004; 27: 260-267Abstract Full Text Full Text PDF PubMed Scopus (146) Google Scholar, 11Rosse RB Deutsch LH Deutsch SI Medical assessment and laboratory testing in psychiatry.in: Sadock BJ Sadock VA 7th ed. Kaplan and Sadock's Comprehensive Textbook of Psychiatry. Vol 1. Lippincott, Williams & Wilkins, Philadelphia, PA2000: 732-755Google Scholar, 12Verstraete AG Detection times of drugs of abuse in blood, urine, and oral fluid.Ther Drug Monit. 2004; 26: 200-205Crossref PubMed Scopus (349) Google Scholar.DrugTimeAlcohol7–12 hAmphetamine48 h Methamphetamine48 hBarbiturate Short-acting (eg, pentobarbital)24 h Long-acting (eg, phenobarbital)3 wkBenzodiazepine Short-acting (eg, lorazepam)3 d Long-acting (eg, diazepam)30 dCocaine metabolites2–4 dMarijuana Single use3 d Moderate use (4 times/wk)5–7 d Daily use10–15 d Long-term heavy smoker>30 dOpioids Codeine48 h Heroin (morphine)48 h Hydromorphone2–4 d Methadone3 d Morphine48–72 h Oxycodone2–4 d Propoxyphene6–48 hPhencyclidine8 d Open table in a new tab Adulterating, substituting, and diluting urine samples are common practices used to avoid detection of drug use. Understanding specific characteristics of a urine specimen can help in identifying false-negative results. The first step in evaluating a urine sample is documentation of the appearance and color. Urine specimens should be shaken to determine whether such substances as soap have been added to the urine. Excessive bubble formation that is long lasting can indicate an attempt to adulterate the specimen.13Warner A Interference of common household chemicals in immunoassay methods for drugs of abuse.Clin Chem. 1989; 35: 648-651PubMed Google Scholar Liquid drain cleaner, chlorine bleach, liquid soap, ammonia, hydrogen peroxide, lemon juice, and eyedrops have been used to manipulate the urine. Other commercial products containing glutaraldehyde, sodium or potassium nitrate, peroxide and peroxidase, and pyridinium chlorochromate (PCC) are being sold to falsify urine specimens.14Jaffee WB Trucco E Levy S Weiss RD Is this urine really negative? A systematic review of tampering methods in urine drug screening and testing.J Subst Abuse Treat. 2007 Jul; 33 (Epub 2007 Jan 16.): 33-42Abstract Full Text Full Text PDF PubMed Scopus (103) Google Scholar Tetrahydrocannabinol (THC) assays tend to be themost sensitive for adulterants causing false-negative results.15Eskridge KD Guthrie SK Clinical issues associated with urine testing of substances of abuse.Pharmacotherapy. 1997; 17: 497-510PubMed Google Scholar Normally, urine specimens range from pale yellow to clear depending on concentration.16Casavant MJ Urine drug screening in adolescents.Pediatr Clin North Am. 2002; 49: 317-327Abstract Full Text Full Text PDF PubMed Scopus (29) Google Scholar Urine specimens collected in the early morning are the most concentrated and often provide the most reliable information.10Heit HA Gourlay DL Urine drug testing in pain medicine.J Pain Symptom Manage. 2004; 27: 260-267Abstract Full Text Full Text PDF PubMed Scopus (146) Google Scholar Unusual colors in urine samples can be due to medications, foods, or diseases and should be noted on documentation that accompanies the specimen for evaluation.17Hammett-Stabler CA Pesce AJ Cannon DJ Urine drug screening in the medical setting.Clin Chim Acta. 2002; 315: 125-135Crossref PubMed Scopus (93) Google Scholar The urine specimen temperature should be recorded within 4 minutes of collection; the temperature should be 32°C to 38°C initially and can remain warmer than 33°C for up to 15 minutes.16Casavant MJ Urine drug screening in adolescents.Pediatr Clin North Am. 2002; 49: 317-327Abstract Full Text Full Text PDF PubMed Scopus (29) Google Scholar Temperatures outside this range can indicate that a substituted urine sample was used. The pH for normal urine fluctuates throughout the day but usually is in the range of 4.5 to 8.0. Specimen contamination should be suspected if the pH level is less than 3 or greater than 11 or if the specific gravity is less than 1.002 or greater than 1.020.16Casavant MJ Urine drug screening in adolescents.Pediatr Clin North Am. 2002; 49: 317-327Abstract Full Text Full Text PDF PubMed Scopus (29) Google Scholar Creatinine concentrations in normal human urine should be greater than 20 mg/dL. Urinary creatinine concentrations of less than 20 mg/dL are considered dilute, whereas concentrations of less than 5 mg/dL are inconsistent with human urine.10Heit HA Gourlay DL Urine drug testing in pain medicine.J Pain Symptom Manage. 2004; 27: 260-267Abstract Full Text Full Text PDF PubMed Scopus (146) Google Scholar Urinary nitrite levels should be less than 500 μg/mL.16Casavant MJ Urine drug screening in adolescents.Pediatr Clin North Am. 2002; 49: 317-327Abstract Full Text Full Text PDF PubMed Scopus (29) Google Scholar If adulteration is suspected or results fall outside these ranges, another specimen should be collected under direct, observed supervision. Devices such as the Intect 7 (Branan Medical Corp, Irvine, CA), Mask Ultra Screen (Kacey, Asheville, NC), AdultaCheck 4, and AdultaCheck 6 (both from Chimera Research and Chemical Inc, Tampa, FL) have been developed to assess the integrity of urine samples.14Jaffee WB Trucco E Levy S Weiss RD Is this urine really negative? A systematic review of tampering methods in urine drug screening and testing.J Subst Abuse Treat. 2007 Jul; 33 (Epub 2007 Jan 16.): 33-42Abstract Full Text Full Text PDF PubMed Scopus (103) Google Scholar These tests all detect validity parameters, such as creatinine and pH, but vary in their detection of adulterants, such as bleach, glutaraldehyde, PCC, nitrites, and oxidants. Two recent studies have shown the Intect 7 to be the most sensitive for adulterations because it can detect bleach, PCC, and vinegar.18Dasgupta A Chughtai O Hannah C Davis B Wells A Comparison of spot tests with AdultaCheck 6 and Intect 7 urine test strips for detecting the presence of adulterants in urine specimens.Clin Chim Acta. 2004; 348: 19-25Crossref PubMed Scopus (28) Google Scholar, 19Peace MR Tarnai LD Performance evaluation of three on-site adulterant detection devices for urine specimens.J Anal Toxicol. 2002; 26: 464-470Crossref PubMed Scopus (35) Google Scholar These devices are often used in conjunction with urine drug testing. The DHHS guidelines for workplace urine testing include 5 mandated drugs of abuse (amphetamines, cannabinoids, cocaine, opiates, and PCP); however, several other substances can be abused (eg, benzodiazepines), warranting screening for more than the 5 mandated drugs of abuse. Urine drug screens for alcohol, benzodiazepines, methadone, and TCAs could be of interest to clinicians in various settings and are also discussed in this article. Table 31Tests for drugs of abuse.Med Lett Drugs Ther. 2002; 44: 71-73PubMed Google Scholar, 8Woelfel JA Drug abuse urine tests: false-positive results.Pharmacist Lett/Prescribers Lett. 2005; 21: 210-314Google Scholar, 16Casavant MJ Urine drug screening in adolescents.Pediatr Clin North Am. 2002; 49: 317-327Abstract Full Text Full Text PDF PubMed Scopus (29) Google Scholar, 20Hawks Rl Chaign CN Urine Testing for Drugs of Abuse. Department of Health and Human Services, National Institute on Drug Abuse, Rockville, MD1986http://www.nida.nih.gov/pdf/monographs/73.pdfGoogle Scholar, 21Cody JT Precursor medications as a source of methamphetamine and/or amphetamine positive drug testing results.J Occup Environ Med. 2002; 44: 435-450Crossref PubMed Scopus (51) Google Scholar, 22Colbert DL Possible explanation for trimethobenzamide cross-reaction in immunoassays of amphetamine/methamphetamine [letter].Clin Chem. 1994; 40: 948-949PubMed Google Scholar, 23Gilbert RB Peng PI Wong D A labetalol metabolite with analytical characteristics resembling amphetamines.J Anal Toxicol. 1995; 19: 84-86Crossref PubMed Scopus (24) Google Scholar, 24Grinstead GF Ranitidine and high concentrations of phenylpropanolamine cross react in the EMIT monoclonal amphetamine/methamphetamine assay.Clin Chem. 1989; 35: 1998-1999PubMed Google Scholar, 25Jones R Klette K Kuhlman JJ et al.Trimethobenzamide cross-reacts in immunoassays of amphetamine/methamphetamine [letter].Clin Chem. 1993; 39: 699-700PubMed Google Scholar, 26Kelly KL Ranitidine cross-reactivity in the EMIT d.a.u. Monoclonal Amphetamine/Methamphetamine Assay [letter].Clin Chem. 1990; 36: 1391-1392PubMed Google Scholar, 27Levine BS Caplan YH Isometheptene cross reacts in the EMIT amphetamine assay.Clin Chem. 1987; 33: 1264-1265PubMed Google Scholar, 28Manzi S Law T Shannon MW Methylphenidate produces a false-positive urine amphetamine screen [letter].Pediatr Emerg Care. 2002; 18: 401Crossref PubMed Scopus (17) Google Scholar, 29Melanson SE Lee-Lewandrowski E Griggs DA Long WH Flood JG Reduced interference by phenothiazines in amphetamine drug of abuse immunoassays.Arch Pathol Lab Med. 2006; 130: 1834-1838PubMed Google Scholar, 30Merigian KS Browning R Kellerman A Doxepin causing false-positive urine test for amphetamine [letter].Ann Emerg Med. 1993; 22: 1370Abstract Full Text PDF PubMed Google Scholar, 31Merigian KS Browning RG Desipramine and amantadine causing false-positive urine test for amphetamine [letter].Ann Emerg Med. 1993; 22: 1927-1928Abstract Full Text PDF PubMed Scopus (12) Google Scholar, 32Nice A Maturen A False-positive urine amphetamine screen with ritodrine.Clin Chem. 1989; 35: 1542-1543PubMed Google Scholar, 33Nixon AL Long WH Puopolo PR Flood JG Bupropion metabolites produce false-positive urine amphetamine results [letter].Clin Chem. 1995; 41: 955-956PubMed Google Scholar, 34Olsen KM Gulliksen M Christophersen AS Metabolites of chlorpromazine and brompheniramine may cause false-positive urine amphetamine results with monoclonal EMIT d.a.u. immunoassay [letter].Clin Chem. 1992; 38: 611-612PubMed Google Scholar, 35Poklis A Hall KV Still J Binder SR Ranitidine interference with the monoclonal EMIT d.a.u. amphetamine/methamphetamine immunoassay.J Anal Toxicol. 1991; 15: 101-103Crossref PubMed Scopus (30) Google Scholar, 36Poklis A Moore KA Response of EMIT amphetamine immunoassays to urinary desoxyephedrine following Vicks inhaler use.Ther Drug Monit. 1995; 17: 89-94Crossref PubMed Scopus (19) Google Scholar, 37Roberge RJ Luellen JR Reed S False-positive amphetamine screen following a trazodone overdose [letter].J Toxicol Clin Toxicol. 2001; 39: 181-182Crossref PubMed Scopus (20) Google Scholar, 38Romberg RW Needleman SB Snyder JJ Greedan A Methamphetamine and amphetamine derived from the metabolism of selegiline.J Forensic Sci. 1995; 40: 1100-1102PubMed Google Scholar, 39Stout PR Klette KL Horn CK Evaluation of ephedrine, pseudoephedrine and phenylpropanolamine concentrations in human urine samples and a comparison of the specificity of DRI amphetamines and Abuscreen online (KIMS) amphetamines screening immunoassays.J Forensic Sci. 2004; 49: 160-164Crossref PubMed Google Scholar, 40Weintraub D Linder MW Amphetamine positive toxicology screen secondary to bupropion.Depress Anxiety. 2000; 12: 53-54Crossref PubMed Scopus (21) Google Scholar, 41Fraser AD Howell P Oxaprozin cross-reactivity in three commercial immunoassays for benzodiazepines in urine.J Anal Toxicol. 1998; 22: 50-54Crossref PubMed Scopus (23) Google Scholar, 42Pulini M False-positive benzodiazepine urine test due to oxaprozin [letter].JAMA. 1995; 273: 1905-1906Crossref PubMed Scopus (10) Google Scholar, 43Protonix [package insert]. Wyeth, Philadelphia, PA2007Google Scholar, 44la Porte CJ Droste JA Burger DM False-positive results in urine drug screening in healthy volunteers participating in phase 1 studies with efavirenz and rifampin [letter].Ther Drug Monit. 2006; 28: 286Crossref PubMed Scopus (12) Google Scholar, 45Leson G Pless P Grotenhermen F Kalant H ElSohly MA Evaluating the impact of hemp food consumption on workplace drug tests.J Anal Toxicol. 2001; 25: 691-698Crossref PubMed Scopus (57) Google Scholar, 46Rollins DE Jennison TA Jones G Investigation of interference by nonsteroidal anti-inflammatory drugs in urine tests for abused drugs.Clin Chem. 1990; 36: 602-606PubMed Google Scholar, 47Rossi S Yaksh T Bentley H van den Brande G Grant I Ellis R Characterization of interference with 6 commercial delta9-tetrahydrocannabinol immunoassays by efavirenz (glucuronide) in urine [letter].Clin Chem. 2006; 52: 896-897Crossref PubMed Scopus (26) Google Scholar, 48Steinagle GC Upfal M Concentration of marijuana metabolites in the urine after ingestion of hemp seed tea.J Occup Environ Med. 1999; 41: 510-513Crossref PubMed Scopus (9) Google Scholar, 49De Giorgio F Rossi SS Rainio J Chiarotti M Cocaine found in a child's hair due to environmental exposure?.Int J Legal Med. 2004; 118: 310-312Crossref PubMed Scopus (18) Google Scholar, 50Hickey K Seliem R Shields J McKee A Nichols JH A positive drug test in the pain management patient: deception or herbal cross-reactivity?.Clin Chem. 2002; 48: 958-960PubMed Google Scholar, 51Mazor SS Mycyk MB Wills BK Brace LD Gussow L Erickson T Coca tea consumption causes positive urine cocaine assay.Eur J Emerg Med. 2006; 13: 340-341Crossref PubMed Scopus (35) Google Scholar, 52O'Neil MJ Smith A Heckelman PE The Merck Index: An Encyclopedia of Chemicals, Drugs, and Biologicals. 13th ed. Merck Research Laboratories, Whitehouse Station, NJ2001Google Scholar, 53Baden LR Horowitz G Jacoby H Eliopoulos GM Quinolones and false-positive urine screening for opiates by immunoassay technology.JAMA. 2001; 286: 3115-3119Crossref PubMed Scopus (70) Google Scholar, 54Baselt RC Casarett LJ Urinary excretion of methadone in man.Clin Pharmacol Ther. 1972; 13: 64-70PubMed Google Scholar, 55Daher R Haidar JH Al-Amin H Rifampin interference with opiate immunoassays [letter].Clin Chem. 2002; 48: 203-204PubMed Google Scholar, 56de Paula M Saiz LC Gonzalez-Revalderia J Pascual T Alberola C Miravalles E Rifampicin causes false-positive immunoassay results for urine opiates.Clin Chem Lab Med. 1998; 36: 241-243Crossref PubMed Scopus (29) Google Scholar, 57Herrera Trevilla P Ortiz Jimenez E Tena T Lora Tamayo C Presence of rifampicin in urine causes cross-reactivity with opiates using the KIMS method [letter].J Anal Toxicol. 1995; 19: 200Crossref PubMed Scopus (6) Google Scholar, 58Lichtenwalner MR Mencken T Tully R Petosa M False-positive immunochemical screen for methadone attributable to metabolites of verapamil.Clin Chem. 1998; 44: 1039-1041PubMed Google Scholar, 59Meatherall R Dai J False-positive EMIT II opiates from ofloxacin.Ther Drug Monit. 1997; 19: 98-99Crossref PubMed Scopus (26) Google Scholar, 60Struempler RE Excretion of codeine and morphine following ingestion of poppy seeds.J Anal Toxicol. 1987; 11: 97-99Crossref PubMed Scopus (71) Google Scholar, 61van As H Stolk LM Rifampicin cross-reacts with opiate immunoassay [letter].J Anal Toxicol. 1999; 23: 71Crossref PubMed Scopus (8) Google Scholar, 62Zebelman AM Troyer BL Randall GL Batjer JD Detection of morphine and codeine following consumption of poppy seeds [letter].J Anal Toxicol. 1987; 11: 131-132Crossref PubMed Scopus (30) Google Scholar, 63Vincent EC Zebelman A Goodwin C Stephens MM What common substances can cause false positives on urine screens for drugs of abuse?.J Fam Pract. 2006; 55 (897.): 893-894PubMed Google Scholar, 64Baselt RC Disposition of Toxic Drugs and Chemicals in Man. 5th ed. Chemical Toxicology Institute, Foster City, CA2000Google Scholar, 65Bond GR Steele PE Uges DR Massive venlafaxine overdose resulted in a false positive Abbott AxSYM urine immunoassay for phencyclidine.J Toxicol Clin Toxicol. 2003; 41: 999-1002Crossref PubMed Scopus (31) Google Scholar, 66Brahm NC Brown RC Venlafaxine usage resulted in a false positive immunoassay for phencyclidine.J Coll Psychiatr Neurol Pharm. 2006; (Accessed December 3, 2007.)http://cpnp.org/_docs/news/20070115.pdfGoogle Scholar, 67Gupta RC Lu I Oei GL Lundberg GD Determination of phencyclidine (PCP) in urine and illicit street drug samples.Clin Toxicol. 1975; 8: 611-621Crossref PubMed Scopus (25) Google Scholar, 68Hull MJ Griggs D Knoepp SM Smogorzewska A Nixon A Flood JG Postmortem urine immunoassay showing false-positive phencyclidine reactivity in a case of fatal tramadol overdose.Am J Forensic Med Pathol. 2006; 27: 359-362Crossref PubMed Scopus (16) Google Scholar, 69Khajawall AM Simpson GM Critical interpretation of urinary phencyclidine monitoring.Adv Alcohol Subst Abuse. 1984 Spring; 3: 65-73Crossref PubMed Scopus (3) Google Scholar, 70Sena SF Kazimi S Wu AH False-positive phencyclidine immunoassay results caused by venlafaxine and O-desmethylvenlafaxine [letter].Clin Chem. 2002; 48: 676-677PubMed Google Scholar, 71Al-Mateen CS Wolf II, CE Falsely elevated imipramine levels in a patient taking quetiapine [letter].J Am Acad Child Adolesc Psychiatry. 2002; 41: 5-6Abstract Full Text Full Text PDF PubMed Scopus (6) Google Scholar, 72Chattergoon DS Verjee Z Anderson M et al.Carbamazepine interference with an immune assay for tricyclic antidepressants in plasma.J Toxicol Clin Toxicol. 1998; 36: 109-113Crossref PubMed Scopus (35) Google Scholar, 73Dasgupta A Wells A Datta P False-positive serum tricyclic antide-pressant concentrations using fluorescence polarization immunoassay due to the presence of hydroxyzine and cetirizine.Ther Drug Monit. 2007; 29: 134-139Crossref PubMed Scopus (22) Google Scholar, 74Fleischman A Chiang VW Carbamazepine overdose recognized by a tricyclic antidepressant assay.Pediatrics. 2001; 107: 176-177Crossref PubMed Scopus (18) Google Scholar, 75Matos ME Burns MM Shannon MW False-positive tricyclic antide-pressant drug screen results leading to the diagnosis of carbamazepine intoxication.Pediatrics. 2000; 105: E66Crossref PubMed Scopus (27) Google Scholar, 76Schussler JM Juenke JM Schussler I Quetiapine and falsely elevated nortriptyline level [letter].Am J Psychiatry. 2003; 160: 589Crossref PubMed Scopus (10) Google Scholar, 77Sloan KL Haver VM Saxon AJ Quetiapine and false-positive urine drug testing for tricyclic antidepressants [letter].Am J Psychiatry. 2000; 157: 148-149PubMed Google Scholar, 78Sorisky A Watson DC Positive diphenhydramine interference in the EMIT-st assay for tricyclic antidepressants in serum [letter].Clin Chem. 1986; 32: 715PubMed Google Scholar, 79Van Hoey NM Effect of cyclobenzaprine on tricyclic antidepressant assays.Ann Pharmacother. 2005 Jul-Aug; 39 (Epub 2005 Jun 14.): 1314-1317Crossref PubMed Scopus (17) Google Scholar, 80Wians Jr, FH Norton JT Wirebaugh SR
Referência(s)