Modafinil is used for

(A) Narcolepsy # MODAFINIL# Narcolepsy Narcolepsy is both a disorder of the ability to sustain wakefulness voluntarily and a disorder of REM sleep regulation The classic "narcolepsy tetrad" consists of excessive daytime somnolence plus three specific symptoms related to an intrusion of REM sleep characteristics (e.g., muscle atonia, vivid dream imagery) into the transition between wakefulness and sleep# Cataplexy: sudden weakness or loss of muscle tone without loss of consciousness, often elicited by emotion. Hallucinations at sleep onset (hypnogogic hallucinations) or upon awakening (hypnopompic hallucinations); and Muscle paralysis upon awakening (sleep paralysis). Narcolepsy: Treatment The treatment of narcolepsy is symptomatic. Somnolence is treated with wake-promoting therapeutics. Modafinil is now the drug of choice, principally because it is associated with fewer side effects than older stimulants and has a long half-life; 20CM00 mg is given as a single daily dose. Modafinil, like other stimulants, increases the release of monoamines, specifically the catecholamines norepinephrine and dopamine, from the synaptic terminals. However, modafinil also elevates hypothalamic histamine levels In the United States, modafinil is approved by the U.S. Food and Drug Administration only for the treatment of narcolepsy, obstructive sleep apnea/hypopnea and shift work sleep disorder. In some countries, it is also approved for idiopathic hypersomnia (all forms of excessive daytime sleepiness where causes can't be established). Older drugs such as methylphenidate (10 mg bid to 20 mg qid) or dextroamphetamine (10 mg bid) are still used as alternatives, particularly in refractory patients.