What Is CNS Depression?

CNS depression is a slowing of your body's central nervous system. It can slow your breathing and heartbeat, which can in turn result in coma or even death. CNS depression happens most often through the use of drugs called CNS depressants. Under a doctor's orders and controlled circumstances, CNS depressants have a medical benefit, but they are common drugs of abuse. CNS depression is a common cause of death in people who overdose on drugs.

Symptoms

• Signs of CNS depression include drowsiness, slower heart rate, loss of motor skills, slower breathing, unclear speech, unclear thinking and unclear vision. They are similar to the signs of drunkenness, and that's no surprise--alcohol is a CNS depressant.

Medical Uses

• Sometimes, there is a medical benefit to causing the central nervous system to calm down. Doctors frequently treat anxiety or sleep disorders by prescribing barbiturates such as Nembutal or benzodiazepines such as Valium and Xanax.

  CNS depressants are also present, in relatively low doses, in over-the-counter cold medicines.

Non-Medical CNS Depression

• CNS depressants include alcohol, opiates, pain medications and other common drugs of abuse. These are dangerous in their own right but doubly so when used in combination. Drinking while using CNS depressants (even with a prescription) can cause coma or death, as can using CNS depressants without a prescription or in a manner inconsistent with a prescription.

Effects

• CNS depressants slow the brain by increasing the activity of a chemical in your brain called gamma aminobutyric acid (GABA). GABA is a neurotransmitter, a chemical that helps your brain cells communicate with one another. GABA slows the brain, so the more it's working, the slower the brain works.

Addiction

• CNS depressants can be dangerous because the body develops a tolerance to them; patients start by taking a small amount, but soon have to take more to feel the effects they desire. This can create a long-term dependence and symptoms of withdrawal--drug addiction. Doctors sometimes intervene by increasing the dosage or changing the prescription or treatment.