Addiction: A chronic, relapsing disease characterized by compulsive drug seeking and use.

Adulterant: A substance, either a biologically active material such as another drug or an inert material, added to a drug when it is formed into a tablet or capsule.

Cardiovascular system: The heart and blood vessels.

Dopamine: A neurotransmitter present in regions of the brain that regulate movement, emotion, motivation, and the feeling of pleasure.

Ecstasy: Common street name for MDMA.

Gastrointestinal system: The stomach and intestines.

Hyperthermia: A potentially dangerous rise in body temperature.

MDMA: Common chemical name for 3,4-methlyenedioxymethamphetamine.

Neurotransmitter: A chemical that acts as a messenger to carry signals or information from one nerve cell to another.

Norepinephrine: A neurotransmitter present in regions of the brain that affect heart rate and blood pressure.

Serotonin: A neurotransmitter used in widespread parts of the brain, which is involved in sleep, movement and emotions

Tolerance: A decrease in the effect of a drug that occurs with repeated administration.