Summary of Agents Potentially Contributing to False Positives on Urine Drug Screens (UDS)

Marijuana Metabolites

 • dronabinol, efavirenz, NSAIDs*, hemp foods: tea, oil, proton pump inhibitors

Cocaine Metabolites 

 • coca leaf teas, topical anesthetics containing cocaine

Opioid Metabolites

 • dextromethorphan, fluoroquinolones, levofloxacin, ofloxacin, poppy seeds, poppy oil, rifampin, quinine

Amphetamines/Methamphetamine (High Rate of False Positives)

 • amantadine, benzphetamine. dextroamphetamine, doxepin, ephedrine, fluoxetine, isometheptene, isoxsuprine, labetalol, I-methamphetamine (OTC nasal inhaler), methylphenidate, MDMA, phentermine, phenylephrine, phenyl-propanolamine, brompheniramine, bupropion, chlorpromazine, desipramine, promethazine, pseudoephedrine, ranitidine, selegiline, thioridazine, trazodone, trimethobenzamide, trimipramine

Benzodiazepines

 • oxaprozin, sertraline

Barbiturates

 • ibuprofen, naproxen

Methadone

 • chlorpromazine, clomipramine, diphenhydramine, doxylamine, thioridazine, ibuprofen, verapamil, quetiapine

Alcohol

• mouthwash, short-chain alcohols, OTC cough products (isopropyI alcohol)

*NSAlDs resulting in false-positive for marijuana mainly consist of ibuprofen and naproxen and modern tests do not result in false positives; + THC concentrations in hemp products are low enough to prevent positive immunoassay results.



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