Doxycycline is a broad-spectrum tetracycline-class antibiotic used in the treatment of infections caused by bacteria and certain parasites. It is used to treat bacterial pneumonia, acne, chlamydia infections, early Lyme disease, cholera, typhus, and syphilis. It is also used to prevent malaria and in combination with quinine, to treat malaria. Doxycycline may be taken by mouth or by injection into a vein.
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