UMEM Educational Pearls

Category: Toxicology

Title: False-Positive Methadone from Tapentadol

Keywords: tapentadol, methadone, false positive, urine toxicology (PubMed Search)

Posted: 1/7/2013 by Bryan Hayes, PharmD (Emailed: 1/10/2013) (Updated: 1/10/2013)
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Several medications can produce a false-positive result for methadone on the urine drug screen: diphenhydramine, doxylamine, clomipramine, chlorpromazine, quetiapine, thioridazine, and verapamil.

Add a new one to the list. Tapentadol, a relatively new opioid analgesic similar to tramadol, can also produce a false-positive result for methadone on certain immunoassays.

A separate study concluded that tapentadol does not affect the amphetamine screen.


Brahm NC, Yeager LL, Fox MD, et al. Commonly prescribed medications and potential false-positive urine drug screens. Am J Health Syst Pharm 2010;67(16):1344-50. [PMID 20689123]

Collins AA, Merritt AP, Bourland JA. Cross-reactivity of tapentadol specimens with DRI methadone enzyme immunoassay. J Anal Toxicol 2012;36(8):582-7. [PMID 22879537]

Tang S, Mullins ME, Braun BM, et al. Can tapentadol cause a false-positive urine drug screen for amphetamine? Clin Toxicol 2012;50(10):1174-5. [PMID 23088194]

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