Efficacy of tadalafil in secondary Raynaud's phenomenon resistant to vasodilator therapy: a double-blind randomized cross-over trial.

Objective: To evaluate the efficacy of tadalafil as add-on therapy in secondary RP resistant to vasodilators.

Methods: Patients with scleroderma and MCTD having four or more RP attacks per week despite being on vasodilators were randomized to receive either placebo or tadalafil (20 mg) on alternate days as add-on therapy to their current vasodilators for 6 weeks. After a 7-day washout, patients were crossed over to the other arm.