To provide long term safety data for rizatriptan in children and adolescents. The primary hypothesis of the study is that rizatriptan is well tolerated in the long term treatment of acute migraine in pediatric patients age 12-17 years.

Inclusion Criteria:

• Patient is between 12 and 17 years of age inclusive at screening Visit 1
• Patient weighs at least 20 kg (44 pounds)
• Patient has had a history of unilateral or bilateral migraine headache with or without aura >6 months with ≥1 to ≤8 mild, moderate or severe migraine attacks per month in the 2 months prior to screening Visit 1
• Patient has a history of migraine defined by International Headache Society (IHS) migraine definitions
• The parent or guardian and patient agree to the patient's participation in the study as indicated by parental/guardian signature on the consent form and patient assent
• For patients taking migraine prophylactic medication, treatment regimen is stable and has been taken for at least 3 months prior to Visit 1

Exclusion Criteria:

• Patient is pregnant or breast-feeding, or is a female expecting to conceive within the projected duration of study participation
• Patient has a history of mild migraine attacks or migraines that resolve in less than 2 hours
• Patient has basilar or hemiplegic migraine headaches
• Patient has >15 headache-days per month OR has taken medication for acute headache on more than 10 days per month in any of the 3 months prior to screening
• Patient has uncontrolled high blood pressure, uncontrolled diabetes, human immunodeficiency virus (HIV), any cancer, or any other significant disease
• Patient has a history cardiovascular problems or stroke
• Patient has either demonstrated hypersensitivity to or experienced a serious adverse event in response to rizatriptan
• Patient has demonstrated hypersensitivity to or experienced a serious adverse event in response to 3 or more classes of drugs (over-the-counter and prescription)
• Patient did not experience satisfactory relief from migraine pain to prior treatment with 2 or more adequate courses of 5-hydroxytryptamine 1 (5HT1) agonists
• Patient has a recent history (within the past year) or current evidence of drug or alcohol abuse or is a "recreational user" of illicit drugs
• Patient is currently taking monoamine oxidase inhibitors, methysergide, or propranolol, and is unable to tolerate withdrawal of these medications for the intervals required
• Patient is currently participating or has participated in a study with an investigational compound or device within 30 days of screening
• Patient is legally or mentally incapacitated