Hangover Headache

It occurs when one has had too much alcohol.
Alcohol makes you go to the toilet and/or sweat more causing dehydration, hence a lack of water in body causes a headache.

Medical Emergency (Hospital)

Methanol poisoning hangover has different symptoms from alcohol poisoning hangover

Has one been drinking alcohol and is one feeling worst than day before?
Symptoms are getting worst (confusion, drowsy, hallucinations, laboured breathing, blurred vision)?

Do not try to sleep it off, and keep print out of travel insurance documents if required

Source: https://www.alcoholandyouni.com

Source: https://www.chss.org.uk

Source: Daily Mail

Symptoms

Does one have:

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