Tranquilizers and other depressants calm nerves and relax muscles. They are bright-colored capsules or tablets that are legally available through a doctor for medical reasons, but can be illegally abused.

When used as prescribed by a doctor, depressants can calm nerves and relax muscles.

Larger or improperly used doses of depressant drugs can cause confusion, lack of coordination, low blood pressure, and slowed heart rate and breathing. Someone who takes them may have slurred speech and an inability to concentrate, and he or she may fall asleep at work or school. Depressants are addictive and withdrawal symptoms include anxiety, sleeplessness, and seizures.

Depressant drugs are very dangerous if taken with alcohol and certain other drugs. Very large doses of depressants can stop breathing and cause death.