Action of Isotretinoin in Acne Rosacea and Gram-Negative Folliculitis

In the early 1980s, a study involving 109 patients demonstrated that isotretinoin was highly effective in treating severe acne, including acne conglobata, acne fulminans, and related conditions, as well as severe rosacea and gram-negative folliculitis. The drug's mechanisms of action include reducing sebaceous gland activity, inhibiting Propionibacterium acnes growth, anti-inflammatory effects, and altering keratinization within follicles. Seventy-nine acne patients treated with doses ranging from 0.05 to 2 mg/kg/day for 12 to 24 weeks showed significant improvement, particularly at higher doses. Thirteen patients with severe rosacea and thirteen with gram-negative folliculitis also experienced marked improvements. The study highlighted isotretinoin's potential to reduce sebum production, bacterial counts, and inflammation, while noting side effects like elevated serum cholesterol and triglycerides, and teratogenic risks requiring contraceptive measures in women of childbearing age. A multicenter cooperative acne study with 136 patients further confirmed isotretinoin's efficacy in reducing sebum production.