Generic term for a group of drugs that are central nervous system depressants with the capacity of relieving anxiety and inducing calmness and sleep. All sedatives/hypnotics may impair concentration, memory, and coordination. Other frequent effects are hangover, slurred speech, incoordination, unsteady gait, drowsiness, dry mouth, decreased gastrointestinal motility , and changes in mood. A reaction of excitement or rage may be produced occasionally. Patients treated over a long period can become psychologically and physically dependent on the drug even if they never exceed the prescribed dose. Withdrawal reactions can be severe and may occur after no more than several weeks of moderate use. Long-term sedative/hypnotic abuse is likely to produce impairments in memory, verbal and nonverbal learning, speed, and coordination that last long after detoxification and, in some, result in a permanent memory disorders. At high doses or when they are abused, many of these drugs can even cause unconsciousness and death.