It advises that the repeated introduction of alcohol and other drugs into the human neurological system triggers a release of dopamine, serotonin, or endorphin in the pleasure centers of the brain. This release upsets the brain's ability to naturally release and replenish its chemical reservoirs. Thus, the person becomes unable to attain feelings of pleasure and well-being without using alcohol or other drugs. Alcohol, taken by itself, has the effect of a central nervous system (CNS) depressant; however, when mixed with other drugs, alcohol can produce additional reactions, such as the following: increase the sedative effect of CNS depressant drugs; inhibit a drug's metabolism by competing with the drug for the same enzymes; and transforming some drugs into toxic chemicals, damaging the liver or organs. A chart summarizes the physiological and clinical attributes of major categories of drugs and their interaction with alcohol. This paper also provides answers to frequently asked questions regarding the interaction of alcohol with other drugs.