Synopsis
Recognise narcolepsy and cataplexy, exclude common causes of excessive sleepiness, obtain valid overnight and daytime sleep testing, and plan safe behavioural, medicine and driving management.
- Narcolepsy causes persistent excessive daytime sleepiness with irresistible sleep episodes; brief naps are often refreshing but do not prevent recurrence later the same day.
- Type 1 narcolepsy is defined by cataplexy and/or documented hypocretin deficiency, whereas type 2 lacks cataplexy and requires objective sleep findings after competing causes are excluded.
- Cataplexy is sudden emotion-triggered loss of muscle tone with preserved awareness, ranging from jaw sag or slurred speech to knee buckling or collapse and usually lasting seconds to minutes.
Key red flags
Sleepiness while driving, operating machinery, working at height or caring alone for a child requires immediate activity restriction and occupational risk planning.
Investigation priorities
Document sleep opportunity, timing, naps, shift work and symptom consistency before objective testing.
Management branches
Sleep attacks or unintended sleep occur repeatedly for at least several months.
- Distinguish sleepiness from fatigue and record night duration, shift work, snoring, apnoea, restless legs, medicines, alcohol, mood and medical illness.
- Ask specifically about emotion-triggered weakness, sleep paralysis, hallucinations, refreshing naps and safety-critical near misses.
Key medicines
ModafinilA common adult specialist regimen is 200 mg daily, given in the morning or divided morning and midday, with adjustment up to 400 mg daily only when response is insufficient. Reduce the dose by half in severe hepatic impairment; people over 65 should usually start at 100 mg daily.
PitolisantStart and titrate once daily in the morning using the licensed weekly schedule, hepatic or renal adjustments and maximum selected by the specialist service.