Doxycycline is a broad-spectrum antibiotic that is employed in the treatment of numerous bacterial infections. NHS information about the medicine doxycycline, including what it's used for, who can take it, how to take it and side effects. Doxycycline oral tablets are used to treat bacterial infections and severe acne, and to prevent malaria. Learn about its side effects, warnings, dosage, and more. Learn about the side effects of doxycycline, from common to rare, for consumers and healthcare professionals. 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 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 an antibiotic that is commonly used to prevent malaria, improve tooth attachment and reduce gum pockets in people who have a dental procedure called scaling and root planing for.