Erythromycin lactobionate, a preparation of erythromycin, is an injection for infusion, and it is also erythromycin that acts after input into the body. Erythromycin lactobionate is a macrolide antibiotic, a bacteriostatic agent, which can also act as a bactericidal agent in high concentration, not only against bacteria, but also against other pathogens, such as certain spirochetes, mycoplasma and chlamydia. Patients who are allergic to penicillin can replace it with erythromycin lactate for the treatment of acute pharyngitis, acute tonsillitis, sinusitis, scarlet fever, and cellulitis caused by sensitive bacteria. There are also specific bacterial infections such as diphtheria, gas gangrene, tetanus, actinomycosis, listeriosis, and also instead of penicillin for syphilis. Erythromycin lactobionate, also can treat Legionnaires’ disease, whooping cough, gonococcal infections, oral anaerobic infections, and Campylobacter jejuni enteritis. In addition, erythromycin lactobionate can treat pneumonia, conjunctivitis and genitourinary tract infections caused by certain mycoplasma and chlamydia.