Last reviewed 2026-04-20 · How we verify

Duragesic (fentanyl)

Synthetic opioid 50-100x more potent than morphine that binds mu-opioid receptors, providing potent analgesia and anesthesia.

Fentanyl is a potent synthetic opioid developed by Paul Janssen in 1960. Medically essential for severe pain and anesthesia, available in multiple innovative delivery systems. Schedule II controlled substance. Available generically.

At a glance

Mechanism of action

Fentanyl is a potent synthetic opioid developed by Paul Janssen in 1960, 50-100 times more potent than morphine by weight. In medical settings, it is invaluable for surgical anesthesia, severe cancer pain, and breakthrough pain in opioid-tolerant patients. The transdermal patch provides sustained 72-hour analgesia. However, illicitly manufactured fentanyl has become the leading cause of drug overdose deaths in the US.

Approved indications

• Acute postoperative pain
• Breakthrough Pain in Opioid Tolerant Patients
• Breakthrough cancer pain
• Chronic Pain with Opioid Tolerance
• General anesthesia
• Local anesthesia
• Pain
• Regional Anesthesia for Postoperative Pain
• Regional Anesthesia for Surgery

Boxed warnings

• WARNING: SERIOUS AND LIFE-THREATENING RISKS FROM USE OF FENTANYL CITRATE INJECTION Addiction, Abuse, and Misuse Because the use of Fentanyl Citrate Injection exposes patients and other users to the risks of opioid addiction, abuse and misuse, which can lead to overdose and death, assess each patient’s risk prior to prescribing and reassess all patients regularly for the development of these behaviors and conditions [see Warnings and Precautions ( 5.1 )]. Life-Threatening Respiratory Depression Serious, life-threatening, or fatal respiratory depression may occur with use of Fentanyl Citrate Injection, especially during initiation or following a dosage increase. To reduce the risk of respiratory depression, proper dosing and titration of Fentanyl Citrate Injection are essential [see Warnings and Precautions ( 5.2 )]. Risks From Concomitant Use With Benzodiazepines Or Other CNS Depressants Concomitant use of opioids with benzodiazepines or other central nervous system (CNS) depressants, including alcohol, may result in profound sedation, respiratory depression, coma, and death. Reserve concomitant prescribing of Fentanyl Citrate Injection and benzodiazepines or other CNS depressants for use in patients for whom alternative treatment options are inadequate [see Warnings and Precautions ( 5.3 ), Drug Interactions ( 7 )]. Cytochrome P450 3A4 Interaction The concomitant use of Fentanyl Citrate Injection with all cytochrome P450 3A4 inhibitors may result in an increase in fentanyl plasma concentrations, which could increase or prolong adverse reactions and may cause potentially fatal respiratory depression. In addition, discontinuation of a concomitantly used cytochrome P450 3A4 inducer may result in an increase in fentanyl plasma concentration. Monitor patients receiving Fentanyl Citrate Injection and any CYP3A4 inhibitor or inducer [see Warnings and Precautions ( 5.4 ), Drug Interactions ( 7 ), Clinical Pharmacology ( 12.3 )] WARNING: SERIOUS AND LIFE-THREATENING RISKS FROM USE OF FENTANYL CITRATE INJECTION See full prescribing information for complete boxed warning. • Fentanyl Citrate Injection exposes users to risks of addiction, abuse, and misuse, which can lead to overdose and death. Assess patient’s risk before prescribing and monitor regularly for these behaviors and conditions ( 5.1 ) • Serious, life-threatening, or fatal respiratory depression may occur with use of Fentanyl Citrate Injection, especially during initiation or following a dose increase. To reduce the risk of respiratory depression, proper dosing and titration of Fentanyl Citrate Injection are essential. ( 5.2 ) • Concomitant use of opioids with benzodiazepines or other central nervous system (CNS) depressants, including alcohol, may result in profound sedation, respiratory depression, coma, and death. Reserve concomitant prescribing for use in patients for whom alternative treatment options are inadequate. ( 5.3 , 7 ) • Concomitant use with CYP3A4 inhibitors (or discontinuation of CYP3A4 inducers) can result in a fatal overdose of fentanyl. ( 5.4 , 7 , 12.3 )

Common side effects

• Nausea
• Dizziness
• Diaphoresis
• Pruritus
• Emesis
• Blurred vision
• Postoperative drowsiness
• Chills and/or shivering
• Restlessness

Serious adverse events

• Respiratory depression
• Apnea
• Rigidity
• Bradycardia
• Respiratory arrest
• Cardiac arrest
• Anaphylaxis
• Serotonin syndrome
• Adrenal insufficiency
• Laryngospasm

Key clinical trials

• Post Operative Pain Control: Continuous Infusion of Morphine vs Fentanyl. Clinical Outcomes (NA)
• Postoperative Benefits of Intraoperative NOL Titration - Pilot (NA)
• Fractional Spinal Anesthesia and Systemic Hemodynamics in Frail Elderly Hip Fracture Patients. (NA)
• Does Audiovisual Distraction Decrease the Use of Hypnotic Drugs During Oocyte Retrieval? (NA)
• Pain, Fentanyl Consumption, and Delirium in Children After Scoliosis Surgery: Dexmedetomidine Versus Midazolam (Phase 4)
• The Effect of mu Opioid Receptor Polymorphism on the Response to Alfentanil During Lithotripsy (NA)
• Comparison of Intrathecal Versus Epidural Fentanyl: Effect of Neuraxial Route of Administration on Fetal Bradycardia in Labor Combined Spinal Epidural Analgesia (Phase 4)
• The Effect of Perioperative Epidural Opioids on Inflammatory Cytokines and Immune Function (NA)

Patents

Primary sources

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