The tetracyclines.

Tetracyclines continue to be used extensively on a world-wide basis because of their unusually broad antimicrobial spectrum and their relative safety. The first generation tetracyclines are used almost exclusively via the oral route; the second generation tetracyclines may be used orally or intravenously. Intramuscular administration is not recommended. Doxycycline is preferred in the treatment of upper respiratory tract infections, atypical pneumonias, intraabdominal/pelvic sepsis or trauma, venereal diseases, and in the treatment of prostatitis. Minocycline is preferred for meningococcal prophylaxis, central nervous system infections (due to susceptible organisms), and in staphylococcal infections (when tetracycline is indicated).