Due to their versatile activities, retinoids have become interesting treatment opportunities of a great variety of infectious and non-infectious skin disorders. The number of possible indications is growing, but controlled trials are often missing; therefore, the level of evidence in most indications is low.
There are a number of trials and case reports about successful use of topical and oral retinoids in chronic inflammatory disorders, including lichen planus, pityriasis rubra pilaris, and lichen sclerosus. Retinoids have been employed for recalcitrant cutaneous lesions induced by the human papilloma virus with encouraging results, although the mechanisms by which the retinoids are capable to induce complete remissions in recalcitrant warts remain obscure. There is also limited experience with retinoids in the treatment of autoimmune disorders such as chronic discoid lupus erythematosus or scleroderma, where collagen production becomes normalized by retinoids.
Further possible indications for retinoid therapy include pigmentary and nail diseases and selected genodermatoses indicating the need for additional clinical trials.