Tetracyclines

Tetracyclines stop bacteria from making proteins by binding their ribosomes. Doxycycline treats respiratory and sexually transmitted infections, rickettsial infections such as Rocky Mountain spotted fever, acne, and anthrax, and helps prevent malaria. Upset stomach, sun sensitivity, and irritation of the esophagus are common, so doses are taken with a full glass of water while staying upright. They can permanently discolor developing teeth, so they are usually avoided in pregnancy and young children unless the infection is serious.

• DoxycyclineKnown brand names include Vibramycin, Doryx, Acticlate, Monodox, Adoxa, Oracea, Periostat, and Targadox.