Answer
Yes, efavirenz in efavirenz/emtricitabine/tenofovir disoproxil has been associated with false-positive urine cannabinoid results in some screening assays; confirmation using a more specific method, such as gas chromatography/mass spectrometry, is recommended.
Sources for this answer
- Efavirenz/Emtricitabine/Tenofovir disoproxil Dr. Reddy's 600 mg/200 mg/245 mg Film-Coated TabletsDr. Reddy's Laboratories (UK) Ltd · emc · SmPC §4.5 Interaction with other medicinal products · Version 12Document updated
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