Nummular headache is one of several relatively uncommon headache syndromes that may occur either as a primary headache or as a headache symptomatic of potentially malignant processes. Careful evaluation for underlying causes is important for these uncommon types of headache.
This topic will review nummular headache. Other types of uncommon primary headache disorders are discussed separately. (See "Primary stabbing headache" and "Primary cough headache" and "Exertional headache" and "Primary headache associated with sexual activity" and "Thunderclap headache" and "Hypnic headache".)
Also called coin-shaped headache, nummular headache is characterized by small circumscribed areas of continuous pain on the head [1,2]. Nummular headaches are generally of mild to moderate intensity and confined to a round or elliptical unchanging area 2 to 6 cm in diameter. The pain is continuous, although in a large minority of cases, spontaneous remissions lasting weeks to months may occur. Superimposed on the continuous pain, lancinating pain may occur that initially lasts seconds but may gradually increase in duration to minutes or hours [1,3,4]. During remissions, the affected area may continue to be allodynic, paresthetic, or hyperesthetic . The parietal region is the area of scalp most often affected .
While nummular headache is typically unifocal, a few patients have been reported with focal head pain in two separate areas [4,6]. One series of 16 patients with nummular headache found a disproportionately high occurrence of comorbid migraine (56 percent) .
Nummular headache is not accompanied by nausea, vomiting, light or sound sensitivity, rhinorrhea, lacrimation, conjunctival injection, or focal neurologic symptoms.