http://pubs.niaaa.nih.gov/publications/Medicine/medicine.htm
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National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health
You’ve probably seen this warning on medicines you’ve taken. The danger is real. Mixing alcohol with certain medications can cause nausea and vomiting; headaches; drowsiness; fainting; loss of coordination; and can put you at risk for internal bleeding, heart problems, and difficulties in breathing. Alcohol also can decrease the effectiveness of a medication or make it totally ineffective.