Glossary
Addiction: A chronic, relapsing disease, characterized by compulsive drug seeking and use and by neurochemical and molecular changes in the brain.
Agonist: A chemical compound that mimics the action of a natural neurotransmitter to produce a biological response.
Analog: A chemical compound that is similar to another drug in its effects but differs slightly in its chemical structure.
Antagonist: A drug that counteracts or blocks the effects of another drug.
Buprenorphine: A mixed opiate agonist/antagonist medication for the treatment of heroin addiction.
Craving: A powerful, often uncontrollable desire for drugs.
Detoxification: A process of allowing the body to rid itself of a drug while managing the symptoms of withdrawal; often the first step in a drug treatment program.
Fentanyl: A medically useful opioid analog that is 50 times more potent than heroin.
Meperidine: A medically approved opioid available under various brand names (e.g., Demerol).
Methadone: A long-acting synthetic medication shown to be effective in treating heroin addiction.
Physical dependence: An adaptive physiological state that occurs with regular drug use and results in a withdrawal syndrome when drug use is stopped; usually occurs with tolerance.
Rush: A surge of euphoric pleasure that rapidly follows administration of a drug.
Tolerance: A condition in which higher doses of a drug are required to produce the same effect as during initial use; often leads to physical dependence.
Withdrawal: A variety of symptoms that occur after use of an addictive drug is reduced or stopped.
Research Reports
This series of reports simplifies the science of research findings for the educated lay public, legislators, educational groups, and practitioners. The series reports on research findings of national interest.
Please note: After September 2013 all NIDA Research Reports will be offered online exclusively. Orders for printed hard copies must be received by August 15, 2013.
Featured Publication
Drugs, Brains, and Behavior - The Science of Addiction
As a result of scientific research, we know that addiction is a disease that affects both brain and behavior.



