Long-term efficacy of sodium oxybate in 4 patients with chronic cluster headache

Cluster headache (CH) manifests with periodic attacks of severe unilateral pain and autonomic symptoms. Nocturnal attacks may cause severe sleep disruption. In about 10%of cases, patients present with a chronic form (CCH), which is often medically intractable. Few attempts have been made to improve headache via pharmacologic modulation of sleep.

In an open-label study, 4 patients with CCH and disturbed sleep received increasing dosages of sodium oxybate (SO), a compound known to consolidate sleep and to increase slow-wave sleep. Response to SO was monitored by serial polysomnography, and actimetry, along with pain and sleep diaries.

SO was effective in all 4 patients as shown by an immediate reduction in frequency (up to 90%) and intensity (>50%) of nocturnal pain attacks and improved sleep quality. These effects were long-lasting in 3 patients (mean 19 months, range 12-29 months) and transient (for 8 months) in one patient. Long-lasting improvement of daytime headaches was achieved with a latency of weeks in 2 patients. SO was safe, with mild to moderate adverse effects (dizziness, vomiting, amnesia, weight loss).

SO may represent a new treatment option to reduce nocturnal and diurnal pain attacks and improve sleep quality in CCH. These data also suggest the interest of treating primary headache syndromes by sleep-manipulating substances.

This study provides Class IV evidence that oral SO at night improves sleep and reduces the intensity and frequency of headaches in patients with CCH.