EFFECT OF SUBCUTANEOUS NARATRIPTAN ON FOREARM BLOOD-FLOW

This randomized, double-blind, placebo-controlled, four-way crossover study was conducted on an in-clinic basis to assess forearm perfusion after subcutaneous (sc) naratriptan and placebo by reserve volume (hyp eremic/baseline) and basal forearm blood flow (FBF) measured by strain gauge plethysmography. Nineteen male and female volunteer migraine su bjects (International Headache Society criteria) received sc naratript an 1 mg, 5 mg, 10 mg, and placebo on four separate study days outside a migraine attack FBF was recorded at baseline, at 7-min intervals pos t-dose up to 1 h (basal) and once after sublingual glyceryl trinitrate administered at 1 h (hyperemic). Vital signs and electrocardiograms w ere recorded at baseline and 15, 30, 45, and 60 min post-dose. There w ere no statistically significant differences in reserve volume (hypere mic/baseline) between any dose of sc naratriptan and placebo. The nara triptan to placebo ratio was 102% (95% CI: 87-120%; p =0.789) for I mg ; 97% (95% CI: 83-114%; p=0.737) for 5 mg; and 92% (95% CI: 79-108%; p = 0.325) for 10 mg. There were no statistically significant differenc es in basal FBI: for any dose compared to placebo. The naratriptan to placebo ratio was 95% (95% CI: 87-104%; p = 0.263) for 1 mg; 94% (95% CI: 86-102%; p=0.142) for 5 mg; and 94% (95% CI: 86-103%; p=0.157) for 10 mg. The percentage of patients reporting adverse events was 53% wi th placebo, 53% with sc naratriptan I mg, 89% with 5 mg and 89% with 1 0 mg. in conclusion, these results suggest that sc naratriptan doses s imilar to and above the oral therapeutic dose equivalent (single oral dose 2.5 mg) have no significant effect on peripheral blood flow as me asured by FBF. Sc naratriptan doses I mg, 5 mg, and 10 mg were well to lerated.