Staccato Prochlorperazine in Migraine (in Clinic)

Inclusion Criteria: * Subjects who have migraine headache with or without aura (diagnosis according to International Headache Society guidelines) for at least 6 months, who have been pain free for at least 48 hours since the end of their last migraine attack, who have a pain rating of Moderate or Severe prior to dosing. Exclusion Criteria: * Subjects who have taken any other migraine or pain medication within 48 hours of randomization, with a history of allergy or intolerance to phenothiazines and related drugs, or are considered by the investigator, for any reason, to be an unsuitable candidate for receiving prochlorperazine, or unable to use the inhalation device, must be excluded.