Pharmacology · Opioids and antagonists
Sufentanil !
A μ opioid of the fentanyl family and one of the most potent in clinical use. It is used in general anaesthesia and epidurally in labour.
Updated 2026-11-01
The figure shows fentanyl, from the same 4-anilidopiperidine family, in the μ receptor bound to its Gi protein; sufentanil occupies the same site.
Mechanism of action
Sufentanil is a μ agonist of the fentanyl family, far more potent than morphine (on the order of a thousand times). It gives strong analgesia in anaesthesia; epidurally, with a local anaesthetic, it relieves labour pain. Its respiratory depression can outlast the measured pain relief.
- Reaches the μ receptor quickly by the intravenous or epidural route
- Activates the μ receptor with great potency
- Strong pain relief in anaesthesia or epidurally
- Respiratory depression can outlast the pain relief
Pharmacokinetics
- Metabolism
- Liver; CYP3A4 is key, so its inhibitors and inducers change its effect.
- Onset and duration
- Rapid onset intravenously.
Indications
- Analgesic adjunct to balanced general anaesthesia in intubated, ventilated patients
- Epidural analgesia for labour and vaginal delivery, with a local anaesthetic
Adverse effects
Common
- Itching
- Flushing and sweating
- Orthostatic hypotension
Contraindications
- Hypersensitivity to sufentanil
Key interactions
- CYP3A4 inhibitors, or stopping inducers
- Can prolong its effect and cause a fatal overdose.
- Benzodiazepines, alcohol and other central nervous system depressants
- Add up to profound sedation, respiratory depression, coma and death.
What is monitored
- Continuous monitoring of breathing, oxygen saturation, blood pressure and heart rate
- In obstetric epidurals: maternal breathing and fetal heart rate
Administration and safety
- Given only by staff trained in anaesthesia and airway management, with continuous monitoring and resuscitation equipment.
- It can cause muscle rigidity, above all of the breathing muscles, managed with a neuromuscular blocker.
- Epidurally, check that the catheter is not in a vessel: intravascular injection causes rigidity and apnoea.
- Its potency makes a dilution or unit error very dangerous: independent double check.
Nursing care
- Watch breathing and sedation even after the pain is controlled.
- Keep naloxone, oxygen and airway equipment at hand.
- In obstetric epidurals, watch the mother and the fetal heart rate.
- Watch for chest-wall rigidity or difficulty ventilating.
Pregnancy and breastfeeding
It is used epidurally in labour; the newborn is watched for respiratory depression.
Test yourself
Think of the answer, then tap the question to see it.
What happens if an epidural dose of sufentanil is accidentally injected into a vessel?
It can cause an overdose with muscle rigidity, above all of the chest wall, and apnoea.
Why is breathing still watched after the pain is controlled?
Because sufentanil's respiratory depression can outlast its pain relief.
How is sufentanil muscle rigidity managed?
With a neuromuscular blocker and ventilatory support.
Related drugs
← Back to the class: Opioids and antagonists
Educational content on how drugs work; not a prescribing guide and no substitute for a health professional's advice. No doses are given.
Sources: SUFENTANIL CITRATE injection, solution (DailyMed (U.S. National Library of Medicine), 2026); Goodman & Gilman's The Pharmacological Basis of Therapeutics, 14th ed., ch. 23 (McGraw Hill, 2023); ATCDDD - ATC/DDD Index (WHO Collaborating Centre for Drug Statistics Methodology, 2026).
Spotted a mistake?We are always improving for the community. Tell us what is wrong and our team will review it.Report a mistake
Representative model, for educational purposes only.