Hi, Cerazette contains Desogestrel which is used as an oral contraceptive pill to prevent pregnancy. It helps to prevent the release and fertilization of the egg by sperm. It is safe for most of the women. Amoxicillin is a penicillin antibiotic that fights bacteria. Amoxicillin is used to treat many different types of infection caused by bacteria like tonsillitis, bronchitis, pneumonia and infections of the ear, nose, throat, skin, urinary tract etc. Most commonly used antibiotics like Amoxicillin don t affect the Progestin only pill Cerazette unless it causes significant vomiting or diarrhea. Amoxicillin induced diarrhea or vomiting may affect absorption of Cerazette and therefore reducing its effectiveness. Otherwise, Amoxicillin hasn t any effect on Cerazette. Both medications can be used at a time. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Zubayer Alam, General And Family Physician