The sleep disturbances are at present a serious medical and social problems. The inappropriate pharmacotherapy of insomnia may be dangerous to health and apart from that usually cause a drug dependance. Orexines and their receptors OX1R, OX2R identified in many structures of the central nervous system play a crucial role in the control of sleep/wake states in humans. Synthesis of almorexant, the double antagonist of orexinergic receptors (DORAs), seemed to be a great progress in the treatment of sleep disorders. It is uniquely important that this experimental drug as opposed to GABA agonists do not disturb the sleep architecture. In spite of its many advantages, pharmaceutical companies abandoned further research, because of its unfavourable tolerability profile. It should be also taken into consideration that the deficit of the brain orexinergic transmission playing an essential role in the pathogenesis of narcolepsy would be corrected by the selective agonists of orexinergic receptors.