Erythrocin is a brand name for the antibiotic medication erythromycin. Erythromycin is an antibiotic that is used to treat a variety of bacterial infections, including pneumonia, bronchitis, and skin infections. There are several other brand names for erythromycin, including Eryc, Ery-Tab, and PCE. Additionally, there are other antibiotics that are similar to erythromycin and can be used as alternatives or in conjunction with erythromycin for bacterial infections. These antibiotics include azithromycin, clarithromycin, and telithromycin. Always consult with a healthcare provider to determine the appropriate antibiotic treatment for your bacterial infection.