Alcohol and Headache: an Update

This update aimed to assess whether recent studies offer confirmation or new insights into the debated relationship between alcoholic drinks (AD) and migraine. Reported discrepancies in alcohol consumption and its triggering role across primary headache types may reflect methodological differences and variations in headache classification by the International Headache Society. Recent prospective studies focusing on the triggering role of AD, vasodilation as a possible mechanism, alcohol consumption patterns, alcohol infusion, and alcohol-induced analgesia were evaluated and discussed. These studies largely confirm the limited role of AD as a triggering factor for migraine. In addition, recent evidence once again highlights the lower consumption of AD among migraine patients, raising the question of whether this finding reflects reverse causality, rather than a protective effect of avoidance. Although many substances have been tested for their ability to provoke migraine and induce cerebrovascular dilatation, ethanol—a natural vasodilator—has never been systematically tested in migraine patients. Some studies show that ethanol infusion does not provoke headache within 5 to 8 hours, but may induce a delayed hangover headache in certain individuals. Finally, despite evidence that moderate alcohol consumption may have analgesic effects and be associated with reduced chronic pain, it remains unclear why this does not occur in migraine patients.