1. Addiction is characterized by compulsive drug use despite harmful consequences. Drugs change the brain's reward system, leading people to need the drug just to feel normal.
2. There are substance addictions like alcohol, tobacco, and drugs as well as behavioral addictions like gambling. Drug addiction is a chronic relapsing disease.
3. Most drugs affect the brain's reward circuit by flooding it with dopamine, causing intense pleasure and motivation to repeat use. A combination of risk factors influences the likelihood someone will become addicted.