Alcohol is rapidly absorbed and quickly enters the water compartment of all body tissues where it produces a number of effects including altering lipid membranes and increasing GABAergic and antagonizing glutamatergic transmission in brain. It is rapidly metabolized to CO2 and water. After 1-2 drinks, alcohol produces decreased inhibition and concentration with increased sociability. With 3-4 drinks, there is impaired reasoning and motor function. With 10 drinks or more, there is stupor or even possibly death. Genetic variations in alcohol metabolism relate to the probability of developing alcohol dependence, a chronic relapsing disorder and it produces large social, personal, medical and healthcare costs.