Insomnia In the European Union, prolonged-release<unk> (Circadin) is indicated for the treatment of insomnia in children and adolescents age 2 to 18 with autism spectrum disorder (ASD) and Smith–Magenis syndrome, in whom sleep hygiene measures have been insufficient.<unk> reduces the time until onset of sleep and increases sleep duration in children with neurodevelopmental disorders. It is also indicated for the short-term treatment of primary insomnia characterized by poor quality of sleep in people who are aged 55 or over. It is deemed to be a first-line agent for short-term treatment of insomnia in people 55 years old or older. Positions on the benefits of<unk> for insomnia are mixed. A review by the Agency for Healthcare Research and Quality (AHRQ) from 2015 stated that evidence of benefit in the general population was unclear. A review from 2017 found a modest effect on time until onset of sleep. Another review from 2017 put this decrease at six minutes to sleep onset but found no difference in total sleep time.<unk> may improve sleep in people with autism. Children with autism have abnormal<unk> pathways and below-average physiological levels of<unk> <unk> supplementation has been shown to improve sleep duration, sleep onset latency, and night-time awakenings. However, many studies on<unk> and autism rely on self-reported levels of improvement and more rigorous research is needed. While the packaging of<unk> often warns against use in people under 18 years of age, studies suggest that<unk> is also an efficacious and safe treatment for insomnia in people with ADHD, including children. However, larger and longer studies are needed to establish long-term safety and optimal dosing. The American Academy of Sleep Medicine's 2017 clinical practice guidelines recommended against the use of<unk> in the treatment of insomnia due to poor effectiveness and very low quality of evidence. The<unk> receptor agonist medication ramelteon may work as well as<unk>  at greater cost but with different adverse effects, for some sleep conditions. Circadian rhythm sleep disorders<unk> may be useful in the treatment of delayed sleep phase syndrome.<unk> is known to reduce jet lag, especially in eastward travel. However, if it is not taken at the correct time, it can instead delay adaptation.<unk> appears to have limited use against the sleep problems of people who work shift work. Tentative evidence suggests that it increases the length of time people are able to sleep. REM sleep behavior disorder<unk> is a safer alternative than clonazepam in the treatment of REM sleep behavior disorder – a condition associated with the synucleinopathies like Parkinson's disease and dementia with Lewy bodies. However, clonazepam may be more effective. In any case, the quality of evidence for both treatments is very low and it is unclear whether either are definitely effective. Dementia A 2020 Cochrane review found no evidence that<unk> helped sleep problems in people with moderate to severe dementia due to Alzheimer's disease. A 2019 review found that while<unk> may improve sleep in minimal cognitive impairment, after the onset of Alzheimer's disease it has little to no effect.<unk> may, however, help with sundowning (increased confusion and restlessness at night) in people with dementia. Available forms A bottle of<unk> tablets.<unk> is also available in timed-release and in liquid forms. A prolonged-release 2mg oral formulation of<unk> sold under the brand name Circadin is approved for use in the European Union in the short-term treatment of insomnia in people age 55 and older.<unk> is also available as an over-the-counter dietary supplement in many countries. It is available in both immediate-release and less commonly prolonged-release forms. The compound is available in supplements at doses ranging from 0.3mg to 10mg or more. It is also possible to buy raw<unk> powder by the pound. Immediate-release formulations of<unk> cause blood levels of<unk> to reach their peak in about an hour. The hormone may be administered orally, as capsules, gummies, tablets, or liquids. It is also available for use sublingually, or as transdermal patches.
Melatonin 
Etoperidone
Sertindole
Tropisetron
Zolpidem
Cilansetron
Chloracyzine
Alosetron