Headache is a common presenting complaint to the emergency department accounting for 1-2% of patient visits. Of these headaches, approximately 90% are migraine, tension headache, or combined presentations. The most commonly used migraine therapy in the ED is intravenous prochlorperazine, but its administration requires close nursing observation, a bed, and the insertion of an intravenous catheter. Buccal prochlorperazine represents an alternative form of delivery that enables rapid achievement of therapeutic blood levels and may lead to symptom resolution. In a randomized, controlled, prospective study,the investigators plan to assess the efficacy of buccal versus intravenous prochlorperazine for the initial emergency department treatment of migraine headaches.

Inclusion Criteria:

• Patients between 18-65 years of age evaluated in the emergency department at Harbor-UCLA with migraine headache as defined by the Headache Classification Committee of the International Headache Society. (Patients must have had at least one prior similar headache, with or without nausea, vomiting, aura, photophobia, or phonophobia).
• Only subjects able to consent to treatment will be included.

Exclusion Criteria:

Patients with the following conditions:

• pregnancy
• breastfeeding
• fever greater or equal to 100.4 degrees
• diastolic blood pressure of 105 or higher
• altered mental status
• meningeal signs
• suspicion for intracranial process requiring further investigation
• known allergy to prochlorperazine
• the use of ergotamines, antiemetics, antipsychotics or sedatives in the previous 24 hours of study entry.