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Educational draft · awaiting clinical reviewUse Rapid for revision, not patient-care decisions. Check current national and local guidance and the BNF or BNFC before acting.

Narcolepsy and excessive daytime sleepiness

Psychiatry · UK scope · Sources checked 27 Aug 2026 · Clinical review pending

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Sleepiness with immediate safety risk

Irresistible sleep while driving, operating machinery, supervising vulnerable people or performing safety-critical work creates immediate danger regardless of the final sleep diagnosis.

Action: Advise immediate cessation of driving and hazardous activity, document DVLA notification advice where excessive sleepiness affects driving, secure safe transport or supervision, and arrange urgent assessment after a collision, near miss or rapidly worsening neurological state.

Synopsis

Characterise pathological sleepiness, recognise narcolepsy and cataplexy, arrange valid specialist testing, and manage driving, occupational and prescribing risks while considering common alternative causes.

  • Sleepiness is a propensity to fall asleep; fatigue is exhaustion or low energy without necessarily being able to sleep.
  • Narcolepsy features irresistible sleep episodes, fragmented night sleep and sometimes cataplexy, sleep paralysis and hypnagogic or hypnopompic hallucinations.
  • Cataplexy is brief emotion-triggered loss of muscle tone with consciousness preserved; it may affect jaw, face, knees or the whole body.
  • Always assess actual sleep opportunity, shift pattern, obstructive sleep apnoea, medicines, substances, mood and other sleep disorders before specialist testing.
  • Use a two-week sleep diary and often actigraphy to document adequate sleep and timing before overnight polysomnography followed by a multiple sleep latency test.
  • An MSLT is vulnerable to insufficient sleep, circadian misalignment and medicines; washout and interpretation belong within specialist protocols.
  • People with excessive sleepiness affecting driving must stop driving and notify DVLA; relicensing depends on satisfactory control and current standards.
  • Management combines scheduled naps, stable sleep, risk modification and specialist medicines, with cardiovascular, psychiatric, reproductive and interaction review.

Key red flags

Sleep at the wheel, recurrent near misses or sudden sleep during safety-critical activity requires immediate risk restriction and prompt assessment.

Acute or rapidly progressive somnolence with confusion, focal signs, fever, head injury or respiratory compromise suggests urgent medical disease.

Witnessed apnoeas, severe hypoventilation risk or sedative and opioid co-use may require expedited respiratory and medication review.

New weakness without an emotional trigger, persistent deficit or altered consciousness is not typical cataplexy and needs neurological assessment.

Investigation priorities

01
Two-week diary and actigraphyFirst step

Document adequate sleep opportunity, timing, naps, shift effects and circadian stability before physiological testing.

Management branches

Initial sleepiness reviewProtect and phenotype

A person reports unintended sleep or difficulty staying awake in the daytime.

  1. Address driving, work, machinery and caring risk immediately, distinguishing true sleepiness from fatigue and documenting incidents.
  2. Review sleep opportunity, schedule, apnoea, medicines, substances, mood and narcolepsy features including cataplexy in precise terms.
  3. Begin a two-week diary, correct obvious deprivation and refer to a sleep service when pathological sleepiness or narcolepsy remains likely.

Key medicines

ModafinilStart 200 mg orally daily, taken once in the morning or divided between morning and noon; if response is insufficient, specialist titration may increase this to 400 mg daily in one or two divided doses. Adults older than 65 years should start 100 mg daily, and the dose should be halved in severe hepatic impairment.Contraindicated in uncontrolled moderate-to-severe hypertension and cardiac arrhythmias. Obtain an ECG before treatment and monitor blood pressure and heart rate; discontinue at the first sign of rash and do not restart, and review emergent psychiatric symptoms and misuse risk. Do not use during pregnancy; ensure effective contraception during treatment and for two months after stopping, accounting for reduced effectiveness of steroidal contraceptives.
SolriamfetolTake 75 mg orally once daily on awakening; 150 mg may be considered initially for more severe sleepiness, with increases no more often than every three days to a maximum 150 mg daily. Avoid taking it less than nine hours before bedtime. In moderate renal impairment, start 37.5 mg daily and increase after at least five days only to a maximum 75 mg; in severe renal impairment use 37.5 mg daily, and do not use in end-stage renal disease.Contraindicated after myocardial infarction within the past year, in unstable angina, uncontrolled hypertension, serious cardiac arrhythmias or other serious heart disease, and with a monoamine oxidase inhibitor or within 14 days after it is stopped. Control hypertension before treatment, measure blood pressure and heart rate before and during treatment, and monitor psychiatric symptoms, interactions and misuse risk.
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Sources and review status7 sources · checked 27 Aug 2026 · clinical review pending+
Sources

Sources and review status

National guidance is shown before implementation-dependent detail. Typical adult dose examples remain subject to patient factors, contraindications and the live BNF or specialist protocol. Source check completed 27 Aug 2026; clinical approval remains outstanding.

  • NHS narcolepsy overviewCore symptoms, cataplexy, sleep paralysis and clinical overview.
  • NHS narcolepsy diagnosisSleep history, polysomnography, MSLT and selective hypocretin testing.
  • NICE TA758 solriamfetolNHS treatment sequence for solriamfetol in adult narcolepsy.
  • Modafinil UK product informationLicensed adult narcolepsy dose, specialist assessment, contraindications, interactions and adverse effects.
  • Solriamfetol UK product informationLicensed narcolepsy dose, renal adjustment, cardiovascular contraindications, interactions and monitoring.
  • MHRA modafinil pregnancy warningPregnancy avoidance and effective contraception during treatment and for two months afterwards.
  • GOV.UK excessive sleepiness and drivingStop-driving and DVLA notification requirements when sleepiness affects driving.

Editorial contact: Doctor’s Passport editorial team. Source-check date is separate from clinical approval. Report a content problem · Content changes

Authoring stateRapid draftClinical stateAwaiting reviewJurisdictionUnited Kingdom