[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Pharmacology](https://durgical.com/en/pharmacology/) › [Other hypnotics (melatonin agonists and orexin antagonists)](https://durgical.com/en/pharmacology/classes/other-hypnotics/) › Suvorexant

[Pharmacology](https://durgical.com/en/pharmacology/) · [Other hypnotics (melatonin agonists and orexin antagonists)](https://durgical.com/en/pharmacology/classes/other-hypnotics/)

# Suvorexant

An orexin receptor antagonist for insomnia. It blocks the brain's wake signal; it can cause next-day drowsiness and brief paralysis on falling asleep.

Updated 2026-11-01

- Class: [Other hypnotics (melatonin agonists and orexin antagonists)](https://durgical.com/en/pharmacology/classes/other-hypnotics/)
- Receptor: Orexin receptor type 2 (OX2)
- ATC code: N05CJ01

◎**Orexin receptor type 2 (OX2)**Suvorexant

ⓘ The figure shows suvorexant itself bound to the human OX2 orexin receptor; it also blocks OX1.

**Target in 3D:** Orexin receptor type 2 (OX2). PDB structure 4S0V (RCSB PDB, public domain). [View the structure at RCSB PDB](https://www.rcsb.org/structure/4S0V) · Drag to rotate · pinch to zoom

## Mechanism of action

Orexins are neuropeptides from the hypothalamus that keep the brain awake. Suvorexant blocks orexin 1 and orexin 2 receptors, turning down this wake drive so that sleep can begin and continue, without acting on GABA-A receptors.

- Orexin from the hypothalamus keeps the brain awake
- Suvorexant blocks orexin 1 and 2 receptors
- The wake drive falls: sleep starts and lasts

## Pharmacokinetics

**Absorption**
Given by mouth shortly before bed

## Indications

- Insomnia: trouble falling or staying asleep [Insomnia disorder →](https://durgical.com/en/conditions/insomnia-disorder/)

## Adverse effects

### Common

- Drowsiness and next-day sleepiness
- Headache and dizziness
- Unusual dreams

### Serious (rare, important)

- Brief inability to move or speak on falling asleep or waking (sleep paralysis) and leg weakness
- Complex sleep behaviours (driving or eating while not fully awake)
- Hallucinations, worsening depression or suicidal thoughts

## Contraindications

- Narcolepsy (generally avoided)
- Hypersensitivity to suvorexant

## Key interactions

**Alcohol**
Worse side effects; avoided

**Grapefruit and grapefruit juice**
May change its effect; discussed with the prescriber

## What is monitored

- Next-day alertness and falls
- Mood and suicidal thoughts
- Episodes of sleep paralysis or sudden leg weakness

## Administration and safety

- Given by mouth shortly before bed, only when a full night in bed is possible
- Controlled medicine

## Nursing care

- Check how the person slept, next-morning alertness and falls
- Ask about alcohol and other sedatives
- Teach to take it only when a full night in bed is possible and not to drive the next morning if drowsy
- Teach to report sleepwalking, sleep-driving or other actions done while not fully awake

## Pregnancy and breastfeeding

Data in pregnancy are limited; plans for pregnancy or breastfeeding are discussed with the prescriber.

## Memory aid

Suvorexant: «-orexant = orexin antagonist» – switches off the wake signal; avoid in narcolepsy.

## Test yourself

Think of the answer, then tap the question to see it.

## What does the suffix -orexant indicate?

An orexin receptor antagonist.

## Why is suvorexant generally avoided in narcolepsy?

Narcolepsy is linked to orexin loss; blocking orexin further could worsen it.

## Which unusual effect on waking can suvorexant cause?

Brief inability to move or speak (sleep paralysis).

[Add to my cards (3)](https://durgical.app/estudiar/?add=/en/pharmacology/suvorexant/)

## Related drugs

- [Ramelteon](https://durgical.com/en/pharmacology/ramelteon/)
- [Zolpidem](https://durgical.com/en/pharmacology/zolpidem/)

## Related conditions

- [Insomnia disorder](https://durgical.com/en/conditions/insomnia-disorder/)

[← Back to the class: Other hypnotics (melatonin agonists and orexin antagonists)](https://durgical.com/en/pharmacology/classes/other-hypnotics/)

Educational content on how drugs work; not a prescribing guide and no substitute for a health professional's advice. No doses are given.

Sources: [Suvorexant: MedlinePlus Drug Information](https://medlineplus.gov/druginfo/meds/a614046.html) (MedlinePlus (U.S. National Library of Medicine), 2026); Goodman & Gilman's The Pharmacological Basis of Therapeutics, 14th ed., ch. 22 (McGraw Hill, 2023); [ATCDDD - ATC/DDD Index](https://atcddd.fhi.no/atc_ddd_index/?code=N05CJ01) (WHO Collaborating Centre for Drug Statistics Methodology, 2026); [4S0V: Crystal structure of the human OX2 orexin receptor bound to the insomnia drug Suvorexant](https://www.rcsb.org/structure/4S0V) (RCSB Protein Data Bank, 2015).

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Representative model, for educational purposes only.

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License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/pharmacology/suvorexant/