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Date of last update: 9/5/2017.

Forum Name: Pharmacy & Drug Topics

Question: sulfa drugs and oral contraceptives

 non818 - Mon Oct 18, 2004 11:25 am


I have been taking Sulfamethoxazole every day for the past 15 years. I had heard that this may change the effectivness of birth control pills, is this true? If it is, by how much, and what would be a better form of contraception?

Thanks for your time.
 Theresa Jones, RN - Thu Oct 21, 2004 5:30 am

User avatar Hi non818,
Certain antibiotics ( Sulfamethoxazole being one of them) can decrease the effectiveness of birth control pills. The exact percentage I am unable to say. You may want to consider using a back up method of condoms and spermacide and also talk to your doctor if he/she is unaware that you are taking Sulfamethoxazole.

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