Alcohol is a toxic substance and causes severe dehydration. The liver needs water to get rid of the toxins. This means taking water from other organs including the brain, which causes those throbbing headaches. The depletion of sodium, potassium and glucose causes the rest of the symptoms like fatigue, muscle pains etc. This is called the dehydration. Tips include drinking less alcohol as far as possible?º. Other tips you can try are1) Eat food while drinking alcohol. This slows down the absorption of alcohol 2)Drink a few glasses of water in between while drinking alcohol for a long time- it will help keep you rehydrated and reduce the amount of alcohol you drink. Once you have a few drinks you get thirsty and end up drinking more and more alcohol because of this. 3)Avoid drinking coffee/tea in the morning after as it will dehydrate you further because of the diuretic affect.