U.S. residents entering the United States at international land borders who are carrying a validly obtained controlled substance (other than narcotics such as marijuana, cocaine, heroin, or LSD), are subject to certain additional requirements. If a U.S. resident wants to bring in a controlled substance (other than narcotics such as marijuana, cocaine, heroin, or LSD) but does not have a prescription for the substance issued by a U.S.-licensed practitioner (e.g., physician, dentist, etc.) who is registered with, and authorized by, the Drug Enforcement Administration to prescribe the medication, the individual may not import more than 50 dosage units of the medication into the United States.In other words, things like allergy meds are A-OK if they're OTC in Canada, as long as you don't bring back too much. Not sure about codeine, though; naively I would think it would be classified as a narcotic, but I might be wrong there.
posted by Grither at 5:48 AM on April 23, 2010