An ice-cream headache, also known as brain freeze, cold-stimulus headache, or its given scientific name sphenopalatine ganglioneuralgia (meaning "nerve pain of the sphenopalatine ganglion"), is a form of brief cranial pain or headache commonly associated with consumption (particularly quick consumption) of cold beverages or foods such as ice cream and ice pops. It is caused by having something cold touch the roof of the mouth (palate), and is believed to result from a nerve response causing rapid constriction and swelling of blood vessels or a "referring" of pain from the roof of the mouth to the head. The rate of intake for cold foods has been studied as a contributing factor.

"Ice cream headaches" result from quickly eating or drinking very cold substances. It is commonly experienced when applying ice-cream (or similar) to the roof of the mouth (palate) or when swallowing it. Typically the headache appears in about 10 seconds and lasts about 20 seconds although some people experience much longer lapses of pain, with the pain seeming to relate to the same side of the head as the cold substance was applied to the palate, or to both sides of the head in the case of swallowing. The most effective way to prevent it is to consume the cold food or liquid at a slower rate. Keeping it in one's mouth long enough for the palate to become used to the temperature is also an effective preventative.