Tolerance is a term used to describe an important feature of alcohol addiction. These symptoms generally last between 2 and 4 weeks, but an increased appetite continues for several weeks. As well, tolerance has developed when increasingly larger doses must be administered to obtain the effects observed with the original dose. There is much debate about the causes of addiction. The root of addiction is unresolved emotional trauma. When traumas, be they extreme or mild, are not resolved they leave behind a slew of painful, unprocessed feelings in the unconscious. These feelings are never content to remain silent and instead clamor for release. Drug dependence is characterized by impaired control over the drug, preoccupation with use, continued use despite negative consequence, and sometimes evidence of physical dependence on the drug.

Physical addiction appears to occur when repeated use of a drug alters reward pathways in your brain. The drug addiction causes physical changes to some nerve cells in your brain. Emotional disorders such as anxiety, depression, bipolar disorder or post-traumatic stress disorder often increase the risk of substance abuse and addictive behaviors, especially amongst those who are misdiagnosed or undiagnosed.