Erythromycin is an antibiotic used for the treatment of a number of bacterial infections. This includes respiratory tract infections, skin infections, chlamydia infections, pelvic inflammatory disease and syphilis.

Doxycycline is a tetracycline antibiotic that fights bacteria in the body. Doxycycline is used to treat many different bacterial infections, such as acne, urinary tract infections, intestinal infections, respiratory infections, eye infections, gonorrhea, chlamydia, syphilis, periodontitis (gum disease) and others. Doxycycline is also used to treat blemishes, bumps and acne-like lesions caused by rosacea.

Levofloxacin is an antibiotic used to treat a number of bacterial infections including acute bacterial sinusitis, pneumonia, H. pylori, urinary tract infections, chronic prostatitis and some types of gastroenteritis.

Metronidazole is an antibiotic and antiprotozoal medication. It is used either alone or with other antibiotics to treat pelvic inflammatory disease, endocarditis and bacterial vaginosis. It is effective for dracunculiasis, giardiasis, trichomoniasis and amebiasis.