sentences:  Commonly used antibiotics, either applied to the skin or taken orally, include clindamycin, erythromycin, metronidazole, sulfacetamide, and tetracyclines (e.g., doxycycline or minocycline).Doxycycline 40 milligrams daily (low-dose) appears to have similar efficacy to 100 milligrams daily and has fewer gastrointestinal side effects.However, low-dose doxycycline is not FDA-approved for the treatment of acne.