Abstract
Introduction
The treatment of cluster headache has improved over the last 15 years. Oxygen inhalation (1, 2), and sumatriptan subcutaneous injection (3, 4) are most effective for the acute treatment. Verapamil (5), prednison (6, 7) and lithium (7, 8) are the prophylactic drugs of choice. Despite these treatment options, a considerable number of patients, in particular those with chronic cluster headache, are refractive to current prophylactic agents. Various surgical procedures have been proposed for these patients (9), including sphenopalatine ganglion blockade (10), but still the majority do not find relief. Naratriptan is a new selective 5-HT agonist, developed for the acute treatment of migraine (11). It has also been used for the prevention of chronic daily headache (12) and menstrual migraine (13). In this report, we describe the prophylactic use of naratriptan in a chronic cluster headache patient.
Case report
A 49-year-old man had suffered from episodic cluster headache since 1993, which became chronic in 1997. The diagnoses conform to International Headache Society (IHS) criteria (14). The attack frequency was two attacks during daytime and four attacks at night, lasting 5–10 min when treated with oxygen or sumatriptan injection and approximately 2 h without acute treatment. Previously he had tried prophylactic lithium, methysergide, verapamil, and steroids in tapering doses, which only shortened the attacks, but did not change the frequency. He underwent sphenopalatine ganglion blockade without relief. We started him on 100 mg sumatriptan in the evening to prevent nightly attacks, without result. The medication was changed to an agent with a longer half-life, i.e. naratriptan 2.5 mg. He used oxygen as rescue medication. During the first two nights the attack frequency diminished to, respectively, three and two attacks. After 2 days the nightly attacks disappeared. The daytime attacks became more frequent from the moment we started him on naratriptan, up to six attacks a day. A second dosage was added in the morning to prevent daytime attacks. After 2 weeks he reported a diminished attack frequency of one attack every 2–3 weeks. He started to experience headache-free periods again.
Following a 4-month period of successful treatment, we stopped the naratriptan to rule out spontaneous remission of the cluster. The patient immediately reported a continuous dull headache on the symptomatic side of his head with autonomic features. This headache was similar to the one he always experienced between attacks. After 1 week he started to use naratriptan again with success.
Discussion
Patients suffering from chronic cluster headache are often refractive to the usual prophylactic drugs. Our patient found relief following the introduction of naratriptan on a daily base, after he had suffered from chronic cluster headache for 3 years. We believe the improvement was not due to a coincidental remission of a cluster bout. Although withdrawal of naratriptan after 4 months resulted in the headache the patient usually experienced between attacks and not in the characteristic attacks, we think it is very likely that the remission of cluster headache was due to the naratriptan administration. Obviously the patient was reluctant to await a new series of attacks.
Naratriptan is usually prescribed for the acute treatment of migraine, but because of its pharmacokinetic properties, i.e. long half-life and improved bioavailability in comparison with other 5-HT agonists, we chose this drug for prophylactic therapy (15). This difference in pharmacokinetics may explain why Monstad did not find any efficacy of sumatriptan prophylaxis in cluster headache patients (16). A recent study demonstrated the positive effect of naratriptan as prophylactic treatment for menstrually associated migraine (13).
As far as we know this is the first report of naratriptan as a prophylactic drug in a chronic cluster headache patient. We believe naratriptan may be a promising new prophylactic drug for refractive cluster headache. Provided that safety issues of daily usage are resolved, it may replace other prophylactic drugs in cases of too many side-effects. We recommend a double-blind placebo-controlled study to confirm the efficacy and safety of naratriptan as a preventive drug in cluster headache.