On the contraceptive pill, but also taking antibiotics -Will a pregnancy test work?

The issue of antibiotics reducing a birth controls efficacy is about 1%. The drug researched most is rifampin, but there a list of them from penicillin to griseovulvin to tetracycline. You need to have a backup plan if you are engaging in sex, such as condoms, a spermicide or the use of a diaphragm.This should continue for at least a week after your regimen is stopped. Another important aspect or clinical sign to look for is spotting in your urine. Should this occur you need to contact your health care provider, to assess if you are indeed pregnant.