Question: what to do when you have bad hangover?
Answer: Hydrate. Consuming alcohol causes dehydration by increasing urination. ...  Sugar boost. Alcohol causes low blood sugar. ...  Coffee. Alcohol causes the blood vessels to dilate, which can cause headaches. ...  Multi-vitamin. ...  Go to bed with an empty stomach. ...  Potassium. ...  Stop drinking. ...  Acetaminophen or ibuprofen.