They can distrupt your REM sleep so they should be avoided.
Explanation: REM sleep first occurs about 90 minutes after falling asleep,most of your dreaming occurs during REM sleep, although some can also occur in non-REM sleep. Your arm and leg muscles become temporarily paralyzed, which prevents you from acting out your dreams. As one ages,they sleep less of their time in REM sleep.
Some sleeping pills like benzodiazepine are rapid eye movement (REM) sleep–suppressant medications, and withdrawal often results in episodes of increased REM sleep (REM sleep rebound).
The newer hypnotics zolpidem and zaleplon are benzodiazepine-like agents, exerting effects at the same neurotransmitter GABA (Gamma-aminobutyric acid) receptors sending chemical messages through the brain and the nervous system bringing about regulation in communication between brain cells. The role of GABA is to inhibit or reduce the activity of the neurons or nerve cells.
Aside from disruption of REM sleep, sedative-hypnotic medications (benzodiazepines and non-benzodiazepines) can cause severe allergic reaction, facial swelling, memory lapses, hallucinations, suicidal thoughts or actions, and complex sleep-related behaviors like sleep-walking, sleep-driving (driving while not fully awake, with no memory of the event) and sleep-eating (eating in the middle of the night with no recollection, often resulting in weight-gain),respiratory depression in patients with pulmonary disease and may lose sleep-inducing efficacy with prolonged use.
