The role of nerve blocks and botulinum toxin injections in the management of cluster headaches.

Cluster headache (CH) is a primary headache syndrome that is classified with the trigeminal autonomic cephalalgias. CH treatment involves three steps: acute attack management, transitional therapy, and preventive therapy. Greater occipital nerve block has been shown to be an effective alternative bridge therapy to oral steroids in CH. Botulinum toxin type A has recently been studied as a new preventive treatment for patients with chronic CH, with limited success.