Addiction: A chronic, relapsing disease characterized by compulsive drug seeking and use despite serious adverse consequences, and by long-lasting changes in the brain.
Anesthetic: An agent that causes insensitivity to pain and is used for surgeries and other medical procedures.
Attention deficit hyperactivity disorder (ADHD): A disorder that typically presents in early childhood, characterized by inattention, hyperactivity, and impulsivity.
Central nervous system (CNS): The brain and spinal cord.
Craving: A powerful, often uncontrollable desire for drugs.
Dopamine: A brain chemical, classified as a neurotransmitter, found in regions that regulate movement, emotion, motivation, and pleasure.
Neurotransmitter: A chemical produced by neurons that carry messages from one nerve cell to another.
Psychosis: A mental disorder characterized by delusional or disordered thinking detached from reality; symptoms often include hallucinations.
Rush: A surge of pleasure (euphoria) that rapidly follows the administration of some drugs.
Stimulants: A class of drugs that enhance the activity of monoamines (such as dopamine and norepinephrine) in the brain, increasing arousal, heart rate, blood pressure, and respiration, and decreasing appetite; includes some medications used to treat attention deficit hyperactivity disorder (e.g., methylphenidate and amphetamines), as well as cocaine and methamphetamine.
Tolerance: A condition in which higher doses of a drug are required to produce the same effect achieved during initial use; often associated with physical dependence.
Toxic: Causing temporary or permanent effects detrimental to the functioning of a body organ or group of organs.
Withdrawal: Symptoms that occur after chronic use of a drug is reduced abruptly or stopped.
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.