What should you know about a pounding headache after drinking?

Alcohol can increase fluid loss, disturb sleep and irritate the stomach. It may also widen blood vessels or trigger headache in people who are sensitive to it. Dehydration, missed meals and a hot environment can intensify the next-day discomfort. The headache should not automatically be attributed to alcohol: a blocked nose, fever or cough may indicate Common Cold or COVID-19, while heat exposure can cause Heat Exhaustion. A repeated pattern may be useful information for a clinician.

Sip water or an oral rehydration drink and eat a light meal if you can tolerate it. Rest in a cool, quiet place and avoid more alcohol. Do not drive if you remain dizzy, drowsy or unsteady. Check the label before taking a pain reliever, because alcohol and some medicines can affect the stomach, liver or alertness. If vomiting continues, seek advice rather than trying to replace fluids quickly.

Get emergency help if the headache followed a fall or blow to the head, is sudden and extreme, or comes with confusion, difficulty waking, seizure, weakness, trouble speaking, stiff neck or vision loss. Seek urgent help for repeated vomiting, inability to keep fluids down, fainting, breathing problems or signs of severe heat illness. These features need assessment even when drinking preceded them.

Could my medicines or health conditions make alcohol-related headache more concerning? How can I replace fluids safely? What symptoms would suggest infection or heat illness instead? Would keeping a drink-and-symptom diary help identify a trigger?