Divalproex sodium in the preventative treatment of cluster headache

Objective: To assess the efficacy and safety of the long-term use of divalproex sodium in the preventative treatment of cluster headache. Design: Long-term, open-label prospective study of divalproex sodium in the preventative treatment of chronic and episodic cluster headache. Setting: The outpatient program at the Diamond Headache Clinic. Patients who had been refractory to standard therapies for the preventative treatment of chronic cluster headache were enrolled. Patient selection: Patients with episodic cluster headache were enrolled if they had contraindications to the Use of standard therapies for episodic cluster headache including methysergide, ergotamine, and corticosteroids. Main outcome measures: Change in the frequency of cluster headache attacks compared to the 1-month period before beginning divalproex sodium for patients with chronic cluster headaches. For patients with episodic cluster headache, the main outcome measure was the change in frequency of cluster headache attacks as compared to the usual number of cluster headache attacks occurring during the prior untreated period. Results: Chronic cluster headache frequency declined by a mean of 53.9 percent. For episodic cluster headache, the reduction was 58.6 percent. Chronic cluster patients average 11.1 months on therapy. Six patients with chronic cluster headache experienced complete remission of their headaches and were able to discontinue preventative medications without cluster headache recurrence for at least 6 months. The mean dose of divalproex sodium was 826mg for chronic cluster headache treatment. For episodic cluster headache, the mean dose was 850mg. Conclusion: Divalproex sodium is a successful therapeutic agent with excellent tolerability for the treatment of chronic cluster headache. It was also successful in the limited population of episodic cluster headache patients enrolled in this study.