Doxycycline is a tetracycline antibiotic. It works by slowing the growth of bacteria in the body.
Doxycycline is used to treat many different bacterial infections, such as urinary tract infections, acne, gonorrhea, and chlamydia, periodontitis (gum disease), and others. It may be used in combination with other medicines to treat certain amoeba infections.
Doxycycline may also be used for other purposes not listed in this medication guide.
Do not use this medication if you are pregnant. It could cause harm to the unborn baby, including permanent discoloration of the teeth later in life. Doxycycline can make birth control pills less effective. Use a second method of birth control while you are taking doxycycline to keep from getting pregnant. Doxycycline passes into breast milk and may affect bone and tooth development in a nursing baby. Do not take this medication without telling your doctor if you are breast-feeding a baby. Do not use this medication if you are allergic to doxycycline, or to similar medicines such as demeclocycline (Declomycin), minocycline (Dynacin, Minocin, Solodyn, Vectrin), or tetracycline (Brodspec, Panmycin, Sumycin, Tetracap). Before taking doxycycline, tell your doctor if you have liver or kidney disease. You may not be able to take doxycycline, or you may need a dose adjustment or special tests during treatment. Do not give doxycycline to a child younger than 8 years old. Doxycycline can cause permanent yellowing or graying of the teeth, and it can affect a child's growth. Throw away any unused doxycycline when it expires or when it is no longer needed. Do not take any doxycycline after the expiration date printed on the bottle. Expired doxycycline can cause a dangerous syndrome resulting in damage to the kidneys.