Preventive treatment for cluster headache

Preventive treatments may be used continuously for chronic cluster headache or intermittently for episodic cluster headache. In predictable episodic cluster headache it is prudent to build up to a therapeutic dose in the 2 to 6 weeks before the expected onset of headaches. Continue treatment at the effective dose during the bout of cluster headache, then taper the dose the month after the cluster headache is predicted to have resolved.

First-line drugs for preventing cluster headache include verapamil, topiramate, gabapentin and melatonin (high dose). Drug doses in cluster headache may need to be titrated faster than in acute migraine. Attaining a therapeutic dose swiftly must be balanced with the adverse effects (especially sedation), which may be more pronounced with rapid titration.

Of these first-line drugs, verapamil has fewer adverse effects and so is recommended as the first drug to try. Verapamil can cause heart block, especially at the doses needed to treat cluster headache. Heart block may not appear until 10 days after starting, or increasing the dose of, verapamil. Before starting verapamil, perform an electrocardiograph (ECG) to exclude heart block, marked bradycardia and prolonged PR interval. Always repeat the ECG before increasing the dose of verapamil.

Anecdotally, immediate-release verapamil is more effective in cluster headache than the sustained-release preparation. Use:

Higher doses (up to 720 mg daily) of verapamil may be used with expert advice.

Lithium is effective for cluster headache, but is not first-line due to its toxicity (the serum concentration of the drug and the patient's thyroid and kidney function must be monitored).

Neuromodulation (eg occipital nerve stimulator, deep brain stimulation with a posterior inferior hypothalamic target)¹ may be considered in refractory cases—refer for expert advice.