Narcolepsy

Narcolepsy forms a part of the differential diagnosis. It is less common than somnambulism, affecting <0.1% of the population. It is a neurological condition caused by a loss of inhibition of rapid eye movement (REM) sleep. It has four main features: irresistible attacks of sleep at inappropriate times, cataplexy (sudden loss of muscle tone when intense emotion occurs, leading to collapse), hypnogogic/ hypnopompic hallucinations (hallucinations that occur on falling asleep and waking respectively) and sleep paralysis. Not all cases of narcolepsy have all four features. When forming a diagnosis, factors that point to hypersomnia are sleeps that have a gradual onset, are worse in the mornings and rarely occur in unusual places. Factors that suggest narcolepsy are a short duration of sleep (10-20 minutes), the inability to control sleep attacks and interrupted night-time sleep, as well as the four main features. Management falls under the remit of neurologists