Neomycin is an antibiotic in the Aminoglycoside family. It is primarily available as a topical ointment and is used to treat certain types of skin infections. Neomycin is often combined with other antibiotics into combination topical ointments (eg. Neosporin) that are used in first aid skin care.
Topical Neomycin ointment is rarely used as a treatment for acne. Many gram-positive bacteria, including the acne-causing P. acnes bacterium, are naturally resistant to Neomycin and other Aminoglycoside family antibiotics. There is limited clinical research into the effectiveness of topical Neomycin as a treatment for active acne.
Neomycin-containing topical ointments, such as Neosporin, are most commonly used to prevent infection and accelerate healing after draining an acne lesion (popping/lancing a pimple).