Drug addiction is a disease that causes compulsive drug seeking and use, despite knowing its harmful consequences. It is a chronic brain disease, which is often relapsing in nature. It is considered as a brain disease as it alters structure and functioning of the brain. How fast you can become addicted varies from one drug to the other. For example, a few drugs such as opioid analgesics can cause addiction more quickly than other drugs. Test your knowledge of drug addiction with the help of the following quiz.