Treatment of disorders of hypersomnolence

In the absence of sleep deprivation (either because of behavioral or medical causes) or pharmacologically induced sleepiness, hypersomnia is a manifestation of one of the central disorders of hypersomnolence, such as narcolepsy types 1 and 2, idiopathic hypersomnia, and recurrent hypersomnias such as Kleine-Levin syndrome. Narcolepsy and most primary hypersomnias are chronic conditions, thus, before committing an individual to chronic, possibly, life-long treatments, an accurate diagnosis is important. The key to effective management of hypersomnia, thus, lies in a thorough history, detailed physical examination, and appropriate diagnostic tests. Secondary causes of hypersomnia are expected to resolve once these disorders are treated. The treatment of central hypersomnias, on the other hand, is guided by a level of diagnostic certainty as to the etiology of the hypersomnia. Narcolepsy, for example, has well defined pathophysiologic and diagnostic criteria, including low levels of hypocretin in cerebrospinal fluid (CSF) and specific findings on a polysomnography/multiple sleep latency test (PSG/MSLT). For these patients, life-long therapy is the norm and involves initiating treatment usually with modafinil, armodafinil, or sodium oxybate, with methylphenidate, amphetamine-like stimulants, atomoxetine, or antidepressants used as second-line therapy. Pharmacologic therapy is usually done in concert with behavioral modifications such as scheduled napping for the best response. On the other hand, the etiology and pathophysiology of non-hypocretin-related hypersomnias (eg, idiopathic hypersomnia, Kleine-Levine syndrome) are unknown. For these reasons, treatment of these disorders is more challenging and less well defined. A trial of modafinil or armodafinil may be considered as first line therapy along with behavioral modifications. Methylphenidate, amphetamine-based stimulants, and even clarithromycin have also been used. There is no effective cure for hypersomnia, and the current therapy is purely symptomatic. Thus, initial patient education, addressing treatment expectations, as well as continued regular follow-up to monitor treatment response are vital to effective management of hypersomnia. The focus of this article is limited to a discussion of treatment of central disorders of hypersomnolence.