INTRODUCTION AND DEFINITION
Cold stimulus headache is a generalized headache that follows exposure of the unprotected head to a cold environment, such as diving into cold water. In addition, cold stimulus headache can be triggered by passing solid, liquid, or gaseous cold materials over the palate and posterior pharynx .
This topic will review clinical aspects of cold stimulus headache. Cranial neuralgias and central causes of facial pain are discussed separately. (See "Overview of craniofacial pain" and "Central neuropathic facial pain" and "Nervus intermedius neuralgia" and "Nummular headache" and "Occipital neuralgia" and "Trigeminal neuralgia".)
The pathophysiology of cold stimulus headache is not completely understood. Cold temperature seems to be a trigeminal trigger  that is followed by possible reflex vasoconstriction .
In a Danish cross-sectional general population survey of people 25 to 64 years old, the lifetime prevalence of cold stimulus headache was 15 percent , while a survey of 13 to 15 year old adolescents from Taiwan found a prevalence of 41 percent . Some studies [3,5-7], but not all , suggest that cold stimulus headache is more common in migraineurs than in the general population.
After exposure to the cold stimulus, the pain begins within seconds, peaks over 20 to 60 seconds, and then subsides in approximately the same time . However, the pain can last up to five minutes in some patients . The headache location is most commonly midfrontal, followed by bitemporal or occipital . When cold stimulus headache occurs in patients with migraine, the pain is more likely to be throbbing  and referred to the usual site of the migraine headache .