Overview
Remifentanil is an ultra-short-acting synthetic opioid analgesic used primarily in anesthesia for its rapid onset and offset of action. It is metabolized by nonspecific tissue and plasma esterases, making it independent of hepatic or renal function for elimination.
Mechanism of Action
Binds to mu-opioid receptors in the central nervous system, inhibiting adenylate cyclase and reducing intracellular cAMP. This hyperpolarizes neurons, decreases neurotransmitter release, and produces analgesia, sedation, and respiratory depression.
Indications
- Induction and maintenance of general anesthesia
- Analgesia in monitored anesthesia care
- Postoperative pain management (when administered continuously)
Dosage
IV administration only. Induction: 0.5-1 mcg/kg/min. Maintenance: 0.05-2 mcg/kg/min. Adjust based on patient response. Bolus doses: 0.5-1 mcg/kg over 30-60 seconds.
Black Box Warning
WARNING: ADDICTION, ABUSE, AND MISUSE; LIFE-THREATENING RESPIRATORY DEPRESSION; ACCIDENTAL EXPOSURE; NEONATAL OPIOID WITHDRAWAL SYNDROME; CYTOCHROME P450 3A4 INTERACTION; RISKS FROM CONCOMITANT USE WITH BENZODIAZEPINES OR OTHER CNS DEPRESSANTS
Contraindications
- Hypersensitivity to remifentanil or other opioids
- Epidural or intrathecal administration due to glycine content
- Use in diagnostic or therapeutic procedures outside monitored anesthesia settings
Side Effects
- Nausea
- Vomiting
- Hypotension
- Bradycardia
- Muscle rigidity
- Pruritus
- Sweating
- Dizziness
- Headache
- Respiratory depression
- Apnea
Interactions
- Benzodiazepines (increased CNS depression)
- Other opioids (additive effects)
- MAO inhibitors (risk of serotonin syndrome)
- CYP3A4 inhibitors (potential increased effects)
- Muscle relaxants (enhanced neuromuscular blockade)