Topiramate is usually used for periods of three to six months for the prevention of migraine. However, a new Spanish study concludes almost 50% of migraineurs may need treatment for more than a year.

In an observational study of migraine patients attending a specialist clinic, 80 consecutive migraine patients who had received prophylactic topiramate for three months were selected. All patients had good response and tolerability to treatment and continued therapy for a further three months, after which drug treatment ceased.

Topiramate was reintroduced if there was a worsening of headache and a further six months of treatment completed before discontinuing again. Patients whose headaches worsened after the second withdrawal received topiramate again and were followed up for at least six months.

In half of patients, headaches did not worsen after the first withdrawal, while the remaining half experienced significant worsening. At the end of the first year of treatment, only 5% of this second group were able to discontinue topiramate use without experiencing an increase in headache frequency after two months.

The authors conclude that around half of patients require topiramate treatment lasting longer than a year and recommended that the current practice of using topiramate for 3-6 months to prevent migraine should be reconsidered in many patients.

^{Pascual J, El Berdei Y, Gomez-Sanchez JC. J Headache Pain 2007. Jan 15 [Epub ahead of print].}

What the WHA thinks:

• Although a small study, with only 38 patients requiring more than a year of topiramate treatment, it provides a useful practice point for physicians.