Previous studies have shown that topiramate is effective in preventing migraine headaches. This is a 6-month observational study to evaluate additional safety data of topiramate in the prevention of migraine in adult patients. The study duration is 6-months, with 5 study visits during the study. Administration of topiramate should be according to current Summary of Product Characteristics (SmPC) and daily clinical practice. The decision to prescribe topiramate is decided by the Health Care Professional and it is independent of the protocol. Based on the investigator's judgement, patients who enter the study should fulfill the criteria for administration of prophylactic treatment. In this study a total number of 80 patients with diagnosed migraine according to the criteria of the International Headache Society HIS (Cephalalgia 1998; 8 (Suppl7) :1-98) will participate. Patients who will be enrolled should be either male or female over 18 years of age, fulfilling the above mentioned criteria and who will agree to sign the written informed consent for the anonymous and confidential use of their medical data with their participation in the study. Methods of evaluation include tolerability, laboratory tests, vital signs and Body Weight and Body Mass Index (BMI). Efficacy by assessing migraine attacks, symptomatic medications and Headache Impact Test (HIT-6). Observational study - No investigational drug administered.