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Tulsa, OK
A 45-year-old female asked:

How long after taking my last bactrim (sulfamethoxazole and trimethoprim) is it safe to drink alcohol? how long after last dose does it stay in your system?

1 doctor answer1 doctor weighed in
Dr. Georgia Latham
Family Medicine 36 years experience
50 hours: The half-life of Bactrim (sulfamethoxazole and trimethoprim) is about 10 hours. A drug should be completely out of your system after 5 half-lives; therefore, Bactrim (sulfamethoxazole and trimethoprim) should be out of your system within 50 hours or just over a day. Alcohol can interact with Bactrim (sulfamethoxazole and trimethoprim) and cause some unpleasant side effects such including: fast heartbeats, warmth or redness under your skin, tingly feeling, nausea, and vomiting.
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Last updated Jan 30, 2021
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