Efficacy Study of PDE-5 Inhibitor and Calcium Channel Inhibitor for the Treatment of Secondary Raynaud Phenomenon

Comparison of Phosphodiesterase-5 Inhibitor and Calcium Channel Inhibitor for the Treatment of Secondary Raynaud Phenomenon, Double Blind, Randomized, Cross-over Trial

The prevalence of Raynaud phenomenon (RP), a reversible vaso-constriction with skin discoloration, is 5-10% in general population. Often conventional measures such as warming up or minimizing exposure to cold are not enough and many patients require treatment with a vasodilator therapy. A recent study showed a good efficacy and safety profile of sildenafil, a selective inhibitor of cGMP specific phosphodiesterase type 5 (PDE5) in RP.

Here, the investigators aim to examine the efficacy and safety of Udenafil, a newer PDE5 inhibitor, as compared to amlodipine, a well known calcium channel blocker, in the treatment of secondary RP in Korean patients.

Inclusion Criteria:

• secondary Raynaud's phenomenon

Exclusion Criteria:

• primary raynaud phenomenon
• active infection
• hypersensitivity to PDE5 inhibitor or Calcium Chanel Blocker (CCB)
• elevated AST/ALT (3 times above the upper normal limit)
• severe renal failure
• patients on nitrite or nitric oxide (NO) donor treatment
• recent history of cerebrovascular accidents, acute myocardial infarction, or coronary artery bypass surgery
• hypotension (less than 90/50 mmHg) or uncontrolled hypertension