Effects of Drug Abuse on the Nervous System

Drugs that affect the central nervous system (CNS) can be very dangerous. As reported by the National Institute of Drug Abuse (NIDA) and the National Institute of Mental Health (NIMH), drug abuse in high dosage or over long periods of time can be seriously damaging. The brain's neurological communication can become permanently rewired, or the brain can stop producing essential chemicals needed for normal functioning. CNS drugs also affect the heart and lungs, including irregular heartbeats, high blood pressure and respiratory problems.

Types

• NIDA reports that the drugs that affect the central nervous system and are most likely to be abused include both prescription and street drugs in these two major categories: stimulants (cocaine, amphetamine, methamphetamine) and depressants (barbiturates, benzodiazepines).

Function

• According to NIDA and NIMH, when drugs are abused, the effects on the nervous system stem from their direct interference with brains' neurotransmitters, which are natural biochemical substances produced by nerve cells and used to communicate between them when regulating the body's thoughts and processes.

Stimulants

• NIDA explains that stimulant drugs--cocaine, methamphetamine, Dexedrine, Ritalin--increase chemicals released by the brain's dopamine neurotransmitter, which is the pleasure neurotransmitter of the brain (see Resources).

Stimulant Drug Effects

• According to NIDA, the chemicals released by stimulant drugs are structurally similar to that of the brain's dopamine neurotransmitter. The flood of chemicals produces a euphoric sensation, interfering with the normal communication from this part of the brain.

Depressants

• NIDA describes depressant drugs--Valium, Xanax, Mebaral, Nembutal--as stimulating the functions of the brain's gamma-aminobutyric acid neurotransmitter (GABA), which is responsible for communicating between cells in an effort to decrease overall brain activity.

Depressant Drug Effects

• According to NIDA, the chemicals released by depressant drugs increase GABA neurotransmitter activity to slow down the brain functions. The result is an overall calming effect, extreme drowsiness and, in large doses, an anesthetic effect.