Orexin Receptor Competitive Antagonists: A Novel target of the Sedative and hypnotics drugs for the pharmacotherapy of Insomnia

Orexins are peptide neurotransmitters which are produced in the lateral and posterior part of the hypothalamus in the brain. There are two Orexin receptors which has been identified till date viz. Orexin 1 (OX 1) and Orexin 2 (OX 2 receptor). Orexins are associated with the sleep-wakefulness and it has been found in the experimental laboratory animals that deficient of Oxerin or the receptors for Orexin are found be associated with narcolepsy and disturbed sleep- awake pattern, day time sleepiness and cataplexy [1]. Orexins are also allied with feeding behaviors, autonomic function and reward in experimental laboratory animals[1]. Recently a number of drugs are targeted towards the Orexin receptors which is a recent target for the Sedative and hypnotics drugs for the treatment of Insomnia viz. Suvorexant, Almorexant, Lemborexant and Filorexant