Fig. 2From: High concentrations of illicit stimulants and cutting agents cause false positives on fentanyl test stripsFentanyl test strip images of interference compounds: FTS were ran with water, cocaine, methamphetamine, MDMA, diphenhydramine capsules, and diphenhydramine tablets and were photographed after 5 min. The testing bar (right side of testing pad) for moderately concentrated samples (approximately > 2 mg/mL) of methamphetamine, MDMA, diphenhydramine capsules, diphenhydramine tablets did not appear indicating false positivesBack to article page