Alcohol, which is consumed in beverages such as liquor, wine and beer, is a chemical called ethanol. Ethanol may cause headaches by several means. First, it is a direct vasodilator; in some individuals vasodilation may cause a headache. Second, ethanol is a natural diuretic; this leads to excretion of salt, vitamins and minerals from the body through the kidneys. Excess consumption of ethanol may produce dehydration and chemical imbalances in the body. Except in “moonshine,” we consume ethanol in beverages that contain other chemicals. These chemicals are called congeners. Congeners impart the specific tastes and flavors that make each beverage unique. These congeners also have a variety of effects that can cause headaches, alter other chemicals in the body, and induce the hangover effect if consumed in excess. Fructose, the naturally occurring sugar from fruits, helps return portions of the body’s chemical balance back to normal following ethanol consumption.
Many with migraine, and most with cluster headaches, are sensitive to alcohol, at times in even small amounts.