While anyone can detox from alcohol, it is only medically necessary if you are physically dependent on alcohol. If you develop physical dependence on a substance like alcohol, you will experience unpleasant and uncomfortable withdrawal symptoms in its absence. Some people who drink alcohol very heavily may develop physical dependence after a few weeks of heavy drinkers, while it may take months or even years for some people to develop physical dependence. For those who are physically dependent on alcohol, a supervised medical detox program provides the safest pathway to ongoing treatment.