Can cough syrup cause a false positive for alcohol on a urine test?
In large amounts, Cough Syrup CAN mark up as a false positive for PCP. NOT Alcohol. This is because the active ingredient in Cough Syrup is “Dextromethorphan” and in large doses can create dissociative effects identical to PCP and Ketamine. You won’t get marked wrongly if you are taking the medicine at the directions on the label, however.
