Does bactrim affect the birth control pill?

Answer 1

Study after study shows that there are no drug interactions between Bactrim and the Birth Control pill; however, some health care providers have made anecdotal reports of pregnancy from a woman taking birth control and antibiotics.

There is no listed interaction between bactrim and plan b but that does not mean there is none. You need to talk to your pharmacist as he has the latested information. Based on what is stated then plan b is just as effective with bactrim as it was without.