The purpose of this study is to determine the effectiveness of melatonin 3 mg compared to placebo and amitriptyline 25 mg in the preventive treatment of migraine.

The investigators propose a study of patients with migraine (episodic) with or without aura, according to the criteria of the International Headache Society (IHS) 2004. This will be a randomized clinical trial, prospective, double-blind, placebo-controlled, comparing the efficacy of melatonin 3 mg and amitriptyline 25 mg for migraine prevention. The length of the inclusion of the study will be 24 months. This study's general objective is: to evaluate the effectiveness of melatonin in the preventive treatment of migraine and compare it to placebo and amitriptyline.

Inclusion Criteria:

• Man or woman 18 to 65 years of age.
• Meets diagnostic criteria criteria of International Headache Society (IHS) 2004 (2) for migraine with and / or without aura.
• Frequency from 2 to 8 migraine attacks per month
• Top of crisis over a year and age of onset less than 50 years of age.
• Patients want to participate in the study, and able to give informed consent.
• If women, the patient must be willing to use an acceptable method of birth control (eg, a hormonal contraceptive, intrauterine device, diaphragm with spermicide or condom with spermicide, or refer abstinence).
• Patient able and willing to remain on their medications throughout the study.
• Accept the guidelines of the study by filling out the diary and clinical scales.

Exclusion Criteria:

• Any medical condition that places the patient at risk with its exposure to melatonin or amitryptiline
• Use of alcohol and drugs.
• Be receiving prophylactic medication in the last three months.
• History of hemiplegic migraine, basilar, Ophthalmoplegic or stroke.
• Headache secondary to head trauma or a whiplash neck injury (whiplash).
• Pregnant or breastfeeding. Women planning to become pregnant or of childbearing age without acceptable method of contraception.
• Women who began taking oral contraceptives or who switched their oral contraceptive regimen in the 6 months prior to the start of the study.
• Allergy or known hypersensitivity to study medication or its components.
• Participation in another clinical study one month before inclusion.