Methotrexate for the treatment of generalized lichen planus.

Lichen planus (LP) is a common pruritic, inflammatory disease that may involve the skin, mucous membranes, nails, and hair follicles.Topical treatments are associated with a good response in limited lesions but in patients with widespread disease, these treatments are usually unsatisfactory. Systemic corticosteroids have long been the treatment of choice for generalized LP but their use is limited in several conditions like old age, systemic diseases such as diabetes mellitus and osteoporosis. Additionally, despite the good results with corticosteroids, recurrence is quite common and sometimes leads to long-term use of such medications. Other systemic treatments that have been tried in cutaneous LP with variable response rates include oral retinoids, azathioprine, Tetracycline, cyclosporine, mycophenolate mofetil, thalidomide, low molecular weight heparin, PUVA or UVB, metronidazol, and biologic agents 1-15. A treatment with a good response rate and safety comparable to corticosteroids but with a lower recurrence rate can be a very good substitute for systemic corticosteroids, especially in old ages and patients with systemic diseases. Methotrexate (MTX) inhibits the action of Dihydrofolate reductase which is a necessary enzyme in the synthesis of Iran J Dermatol 2011; 14: 131-135 Received: September 7,2011 Accepted: December 3, 2011