The presence of cutaneous allodynia may predict response to triptans. Identical randomized double-blind studies were conducted comparing the efficacy of rizatriptan 10 mg or placebo administered within 1 h of headache onset, while pain was mild. The primary endpoint was freedom from pain at 2 h. Presence of symptoms suggesting cutaneous sensitivity (SCS) at baseline and at 2 h post-treatment was recorded. Before treatment, 29% of rizatriptan patients and 22% of placebo patients reported SCS. At 2 h, the percentage of patients with SCS was significantly decreased with rizatriptan. The presence of SCS pre-treatment was not predictive of response to rizatriptan. Most patients with SCS at 2 h were non-responders. Early treatment with rizatriptan significantly reduced the percentage of patients with SCS at 2 h. The presence of SCS at baseline did not predict pain-free response, but presence of SCS at 2 h correlated with lack of a 2-h pain-free response.