I'm on birth control, and I went to the doctor's today because I felt sick and he told me I had bronchitus and prescribed 100 mg of Amoxil 3 times a day for me. I checked on the Planned Parenthood site and it told me that only the antibiotic rifampin made the pill less effective, does anyone know if that's true? And also, I had sex 4 days ago, and I am not sure if the guy ejaculated or not, but if these Amoxil pills do make the pill less effective, could I end up getting pregnant if I had sex before I was on them?

I'm on birth control, and I went to the doctor's today because I felt sick and he told me I had bronchitus and prescribed 100 mg of Amoxil 3 times a day for me. I checked on the Planned Parenthood site and it told me that only the antibiotic rifampin made the pill less effective, does anyone know if that's true? And also, I had sex 4 days ago, and I am not sure if the guy ejaculated or not, but if these Amoxil pills do make the pill less effective, could I end up getting pregnant if I had sex before I was on them?


First of all, rifampin is for megingitis and is no way related to Amoxil. However, Amoxil will lower the effectiveness of the pill. Technically, you could get pregnant from starting the antibiotic today, but it's VERY unlikely.

Be sure to use a back-up method of birth control for AT LEAST 7 days after finishing the antibiotic.

Ok, I'm gonna wait a few days I think before I start them, hopefully ill be safe then. Thanx