An assessment of urine THC immunoassay in healthy volunteers receiving an oral proton-pump inhibitor

Abstract

Introduction: Limitations of urine drug-screening (UDS) by immunoassay include false-positive results. Pantoprazole, a proton-pump inhibitor (PPI), is reported to cause false-positive results for THC on UDS. The objective of this study was to determine if oral PPIs cause false-positive THC results using the THC One Step Marijuana Test Strip^®.

Methods: Eligible healthy volunteers completed a 5-day course of a PPI followed by urine testing using the THC One Step Marijuana Test Strip^®. Phase one included 3 subjects taking pantoprazole 40 mg once daily for 5 days. On day 5, urine specimens underwent THC screening. Phase two included 9 subjects randomized to 5-day supply of once-daily oral esomeprazole 20 mg, lansoprazole 15 mg, or omeprazole 20 mg. All study methods and testing mirrored those in phase one.

Results: All 12 subjects completed the study protocol. All urine samples collected on day 5 were negative for THC in all subjects.

Discussion: Our results demonstrate that oral PPIs did not cause a false-positive THC using the THC One Step Marijuana Test Strip^®. Limitations include small sample size, use of a single commercial immunoassay, and inability to confirm medication compliance. Further, large-scale research using other commercial urine immunoassays is warranted.

Keywords:

• Proton-pump inhibitors
• tetrahydrocannabinol
• false-positive
• urine immunoassay
• pantoprazole

Disclosure statement

No potential conflict of interest was reported by the authors

Additional information

Funding

The present work was financially supported by SUNY Upstate Medical University Department of Emergency Medicine [Award Number 10.13039/100010956].