This is a double-blind, placebo-controlled, randomized, crossover trial comparing MTS with placebo patch. The double-blind trial will be preceded by an enrollment period consisting of two screening visits followed as quickly as possible by a baseline visit. Patients who continue to meet admission criteria at baseline will be randomized into the first of two 4-week treatment periods. We will attempt to reach the highest tolerated dose size of MTS within 2 weeks and then observe the response over the last two weeks of each crossover phase. The double-blind period will be followed by a 180 day open-treatment, flexible-dose phase designed to assess long-term effects.