Pregnant and on antibiotic

Dear Ask The Doctor: I just found out I am pregnant and I have been on sephalexin for 10 days. Can that seriously damage the baby? Also is it possible for a false positive on a pregnancy test?

Dear Elisha: Cephalexin belongs to a class of antibiotics called cephalosporins and is used to treat infections like infections of the ear, tonsils, throat and pneumonia. Though the drug has not been studies in pregnant women, animal studies have shown that it causes negative effects on the fetus. I would suggest that you let your health care provider know that you were on the drug. He or she will consider the benefits and risks of cephalexin during pregnancy before making a recommendation for your particular situation.