Usually, there are few consequences of long-term use of minocycline. Rarely, diffuse fatty degeneration of the liver may be found. An uncommon dermatological problem is the development of gram-negative folliculitis after tetracycline acne therapy is stopped. Also cutaneous pigmentation is a well-recognized side-effect of minocycline therapy. Minocycline-induced cutaneous pigmentation usually occurs after a high cumulative dose. In one recent study, all patients with this side-effect had taken minocycline for more than two years, at the relatively high dose of 200-400 mg per day. (Ref: Sabroe RA et al. Minocycline-induced discoloration of the sclerae. Br J Dermatol 1996;135:314-316.)