Brief Answer:
Yes mestinon may give false positive test for opiates

Detailed Answer:
Thank you for asking

I read your question and i understand your concern. I believe you wanna ask whether Mestinon ( Pyridostigmine) causes false positive of drug screening. If so the answer is yes. There have been reported cases where screening for drugs intake in people who have been taking mestinon have come up false positive.

Commonest drug tests which come under this false positive label are opiates and barbiturates. The drug screen authorities know this interaction and should not be a problem.

Also people who use even slight amount of drugs stays longer in the system if simultaneously on Mestinon because it reduces the clearance and metabolism of the drug.

I hope it helps. Take good care of yourself and dont forget to close the discussion please.

Regards
Khan

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