Consumption of ethanol has a rapid diuretic effect, meaning that more urine than usual is produced, since ethanol inhibits the production of antidiuretic hormone.

Overconsumption can therefore lead to dehydration (the loss of water). It is difficult to replenish the body's fluids using only alcoholic beverages. As large amounts of alcohol are consumed, the diuretic effect causes the body to lose more water than is contained in the beverage.