Failure of a pure anti-platelet drug to decrease the number of attacks more than placebo in patients with Raynaud's phenomenon.

Fifty-eight patients with Raynaud's phenomenon were randomly allocated in a six week double-blind clinical trial in parallel groups to compare the efficacy of a pure antiplatelet agent, ticlopidine (250 mg b.i.d.) with that of a placebo. There was no significant difference between the two treatments in percent re duction of weekly number of attacks and in subjective improvement assessed by both patient and investigator. It is unlikely that platelets are involved in the mechanisms of Raynaud's crisis.