Sleep Disorders Pregnancy: US labelling: there are no available data on use in pregnant women to evaluate for drug-associated risks of major birth defects, miscarriage, or other adverse maternal or fetal outcomes. In animal reproduction studies, oral administration to pregnant rats and rabbits during organogenesis did not cause fetal toxicity or malformation at doses up to 8 and 10 times the maximum recommended human dose of 50 mg, respectively, based on AUC. A pregnancy exposure registry monitors outcomes in women exposed during pregnancy. Verify against UK SPC §4.6.

Daridorexant

Brand names: Quviviq

Daridorexant is an oral dual orexin-receptor antagonist licensed for the treatment of insomnia characterised by symptoms present for several months with substantial daytime impact.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: 25 mg to 50 mg once per night

Route: Oral

Frequency: No more than once per night, taken within 30 minutes of going to bed, with at least 7 hours remaining prior to planned awakening

Max: 50 mg no more than once per night; maximum 25 mg once per night when used with a moderate CYP3A4 inhibitor or in moderate hepatic impairment (Child-Pugh score 7–9)

SOURCE CAVEAT: no UK SPC posology was available in the fetched bundle — this dose is taken from the US prescribing information for QUVIVIQ (daridorexant) and must be verified against the UK SPC before publication. Time to sleep onset may be delayed if taken with or soon after a meal. Avoid concomitant use with strong CYP3A4 inhibitors; the recommended dosage is 25 mg no more than once per night when used with moderate CYP3A4 inhibitors; avoid concomitant use with strong or moderate CYP3A4 inducers. HEPATIC IMPAIRMENT: maximum 25 mg no more than once per night in moderate hepatic impairment (Child-Pugh 7–9); not recommended in severe hepatic impairment (Child-Pugh ≥10). ELDERLY: no dose adjustment is required in patients over 65 years, but the likelihood of somnolence and fatigue increases with age and patients are at higher risk of falls. Reevaluate if insomnia persists after 7 to 10 days. PAEDIATRIC: safety and effectiveness have not been established in paediatric patients. Available as 25 mg and 50 mg film-coated tablets. Source: US FDA prescribing information for QUVIVIQ (Idorsia Pharmaceuticals Ltd), §2 Dosage and Administration.

Dose auto-extracted from US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

Narcolepsy
Known hypersensitivity to daridorexant or any of the components of the product — reactions have included angioedema with pharyngeal involvement

Side effects

Headache — one of the most common adverse reactions (reported in ≥5% of treated patients and at an incidence ≥ placebo)
Somnolence or fatigue — one of the most common adverse reactions; CNS-depressant effects can impair daytime wakefulness and may persist for up to several days after discontinuation
Worsening of depression or suicidal thinking
Sleep paralysis, hypnagogic/hypnopompic hallucinations and cataplexy-like symptoms
Complex sleep behaviours including sleepwalking and sleep driving while not fully awake — discontinue immediately if these occur
Compromised respiratory function — effect on respiratory function should be considered

Interactions

Strong CYP3A4 inhibitors — avoid concomitant use (increased daridorexant exposure and risk of adverse reactions)
Moderate CYP3A4 inhibitors — reduce the dose to a maximum of 25 mg once per night
Strong or moderate CYP3A4 inducers — avoid concomitant use (decreased exposure may reduce efficacy)
Alcohol and other CNS depressants — additive CNS-depressant effects (US labelling §7.1; detail truncated in the fetched source)

Clinical monograph

How it works

It blocks orexin OX1 and OX2 receptors, reducing the wake-promoting drive of the orexin system to facilitate sleep onset and maintenance without classical GABAergic sedation.

Prescribing in practice

Next-morning impairment of driving and alertness can occur, so patients should not drive or undertake skilled tasks until they know how it affects them and should allow sufficient sleep time after dosing.
Avoid concomitant strong CYP3A4 inhibitors, which substantially raise exposure, and co-administration with alcohol or other CNS depressants increases sedation.
Use with caution in those with a history of substance misuse and in significant hepatic impairment; it is taken shortly before bed when a full night's sleep is possible.

Monitoring

No routine laboratory monitoring is required; review ongoing need, daytime functioning and any residual sedation periodically.

Counselling the patient

Take shortly before going to bed and only when you can have a full night's sleep.
Avoid alcohol and beware of next-morning drowsiness affecting driving.
Tell your prescriber if sleep does not improve after a few weeks.

Evidence & guidelines

Randomised controlled trials demonstrated that daridorexant improves sleep onset, maintenance and daytime functioning in chronic insomnia.

Reference: IDARED trials Lancet 2022; 400(10349):347-356; MHRA 2022 approval; ESC Insomnia Guidelines; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Calculators

Pathways