When a medication works right, it boosts your health or helps you feel better. But a drug can bring on problems if it doesn't mix well with something else you put into your body, like another. Doxycycline can interfere with how amoxicillin kills bacteria. We’ll break down the science behind this interaction, what it means for your treatment, and when there might be exceptions. Doxycycline interacts with several common medications, supplements, and foods, which can affect its effectiveness or cause side effects. Avoid taking doxycycline with antacids, calcium supplements, seizure medicine, or iron, as they reduce absorption. Learn what doxycycline is, how it works, and its primary uses in treating bacterial infections. A trusted antibiotic explained clearly. Read on to learn about the common and rare side effects of doxycycline and how to manage them. Doxycycline is used to treat bacterial infections in many different parts of the body. It is also used to treat pimples and abscesses (usually on the face) that are caused by rosacea, also known as acne rosacea or adult acne. Doxycycline and amoxicillin are two commonly prescribed antibiotics, each effective against a range of bacterial illnesses. Questions sometimes arise about the safety and effectiveness of taking multiple medications simultaneously, especially when both are antibiotics. Doxycycline can interact with certain medications, supplements, and foods. Examples include blood thinners, such as warfarin, antacids, birth control pills, certain seizure medications, and dairy. Doxycycline is a tetracycline antibiotic that inhibits bacterial growth and is thought to have anti-inflammatory effects. Doxycycline is used for bacterial infections, including acne, rosacea, urinary and respiratory tract infections, eye infections, gum disease, gonorrhea, chlamydia, and syphilis. Doxycycline is used to treat infections caused by bacteria and certain other infections spread by ticks, lice, mites, and infected animals. Doxycyline is also used to prevent malaria and to treat acne and rosacea (a skin disease that causes redness, flushing, and pimples on the face).