Know about Hypnic Headache

Hypnic headache is a typical type of headache which starts few hours after the person suffering from; fall asleep (few hours after onset of sleep). The spell of hypnic headache lasts for 15 to 30 minutes and may recur again after few hours and patients is awakened again and up to 3 episodes of hypnic headache may occur in one night.

The severity of headache in hypnic headache is generally moderate in intensity and commonly the headache is generalized in nature or not located in a particular part of the head, unlike migraine headache which is typically unilateral in nature. But in some patients with hypnic headache the headache may be unilateral and throbbing type of headache. Hypnic headache is more commonly seen among females and men are affected uncommonly. The common age of onset is over 60 years. The symptoms are typically bilateral and only rarely unilateral.

How to diagnose hypnic headache?

The diagnosis of hypnic headache is mainly by typical symptom and associated hypertension can aid the diagnosis.

What factors can cause/precipitate hypnic headache?

High blood pressure is one of the known causes of hypnic headache, especially in cases of uncontrolled or poorly controlled hypertension. Daytime naps can precipitate hypnic headache and should be avoided.

How hypnic headache is treated?

Hypnic headache can be treated with good result. If patient is hypertensive blood pressure should be well controlled with appropriate anti-hypertensive drugs and 24 hour blood pressure monitoring should be done to detect the hypnic headache and to fully control blood pressure. Avoid daytime naps to prevent aggravation of hypnic headache.

Lithium carbonate at the dose of 200-600 mg per day at bed time gives satisfactory result in hypnic headache. If a patient can not tolerate lithium carbonate due to allergy or adverse effects the alternatives are verapamil (160 mg at bed time) or methysergide (1–4 mg at bedtime), both of which also give good results. Caffeine at the dose of 60 mg or two cups of coffee at bedtime can also be very useful in approximately one-third of patients with hypnic headache. Flunarizine, 5 mg at bedtime also shows effectiveness in treating hypnic headache.