Cutibacterium acnes (formerly Propionibacterium acnes) is the relatively slow-growing, typically aerotolerant anaerobic, Gram-positive bacterium linked to the skin condition of acne. It can also cause chronic blepharitis and endophthalmitis, the latter particularly following intraocular surgery. This bacterium is largely commensal and part of the skin flora present on most healthy adult humans' skin. It is usually just barely detectable on the skin of healthy preadolescents. It lives primarily on, among other things, fatty acids in sebum secreted by sebaceous glands in the follicles. It may also be found throughout the gastrointestinal tract. C. acnes bacteria are susceptible to a wide range of antimicrobial molecules, from both pharmaceutical and natural sources. Antibiotics are commonly used to treat infections caused by C. acnes. Acne vulgaris is the disease most commonly associated with C. acnes infection. The antibiotics most frequently used to treat acne vulgaris are erythromycin, clindamycin, doxycycline, and minocycline.