In many cases, insomnia is caused by another disease or psychological problem. In this case, medical or psychological help may be useful.
Many insomniacs rely on sleeping tablets and other sedatives to get rest. All sedative drugs have the potential of causing psychological dependence where the individual cannot psychologically accept that they can sleep without drugs. Certain classes of sedatives such as benzodiazepines and newer nonbenzodiazepine drugs can also cause physical dependence which manifests in withdrawal symptoms if the drug is not carefully titrated down. In comparing the options, a systematic review found that benzodiazepines and nonbenzodiazepines have similar efficacy which was insignificantly more than for antidepressants. Benzodiazepines had an insignificant tendency for more adverse drug reactions.
The most commonly used class of hypnotics prescribed for insomnia are the benzodiazepines. Benzodiazepines bind unselectively to the GABA receptor. This includes drugs such as temazepam, diazepam, lorazepam, flurazepam, nitrazepam and midazolam. These medications can be addictive, especially after taking them over long periods of time.
Nonbenzodiazepine prescription drugs, including the nonbenzodiazepines zolpidem and zopiclone, are more selective for the GABA receptor and may have a cleaner side effect profile than the older benzodiazepines; however, there are controversies over whether these non-benzodiazepine drugs are superior to benzodiazepines. These drugs appear to cause both psychological dependence and physical dependence, and can also cause the same memory and cognitive disturbances as the benzodiazepines along with morning sedation.
Some antidepressants such as mirtazapine, trazodone and doxepin have a sedative effect, and are prescribed off label to treat insomnia. The major drawback of these drugs is that they have antihistaminergic, anticholinergic and antiadrenergic properties which can lead to many side effects. Some also alter sleep architecture.
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