Causes
Alcoholism is a medical condition. While the exact cause of alcoholism is unknown, research has shown increasing evidence that susceptibility to it may be inherited and the risk of developing this medical condition rises significantly in families with relatives (in particular, parents and siblings) who are dependent on alcohol. Additional risk factors include having a psychiatric condition such as schizophrenia, depression, or anxiety disorders. Poverty, social isolation, and shyness may also be risk factors.
In addition, how one's body processes alcohol can affect the risk of developing a dependence on alcohol. Research has shown that people who need comparatively more alcohol to achieve an effect are more likely to become alcohol dependent.
All drugs affect a "reward mechanism" in the brain. Each time a person uses a drug, they feel good, which tends to make them want to use the drug again. This common feature could explain why people abuse drugs, including alcohol. As with most drugs, though, if you use them regularly, your body tends to require increasing amounts of the substance to achieve the same effect. This is called tolerance, and may be the final factor that contributes to the development of drug or alcohol dependence.