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Fentanyl citrate

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Dose and administration

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Sedation and analgesia: 1-4 micrograms/kg/dose IV slow push, IM.

  • For intubation, use 4 micrograms/kg
  • Repeat as required (usually every 2-4 hours).
  • May be given as a continuous infusion: 1-5 micrograms/kg/hour.

Anaesthesia: 5-50 micrograms/kg/dose.

  • Minor surgery 5-20 micrograms/kg/dose.
  • Major surgery 30-50 micrograms/kg/dose.
                    Fentanyl (micrograms) in 50ml IV solution = 50 x weight (kg) x dose (micrograms/kg/hour)
                                                                                                         IV rate (ml/hour)

Usual strength = 2-10 micrograms/ml.


  1. Intubation
  2. Analgesia
  3. Sedation
  4. Anaesthesia

Contraindications and precautions

  1. Known hypersensitivity to fentanyl and/or other opiates
  2. Bradyarrhythmias
  3. Myasthenia gravis
  4. Caution in preterm infants, especially extreme immaturity
  5. Caution in neonates with hepatic or renal impairment
  6. Caution in nonventilated neonates with respiratory distress
  7. Caution in neonates with raised intracranial pressure

Clinical pharmacology

Fentanyl citrate, a narcotic analgesic, is 50-100 times more potent than morphine. Actions qualitatively similar to those of morphine. Produces a minimum of cortical depression. Alterations in respiratory rate and alveolar ventilation may last longer than analgesic effect. No significant cardiovascular effects at usual therapeutic doses.

Rapid distribution with sequestration in fat. Wide variability in distribution volume (Vd 1-13 L/kg). Extensive binding to human plasma protein. Hepatic metabolism. Excretion via the kidney. Elimination half-life very variable in neonates (6-32 hours). Onset of action almost immediate with IV administration (7-8 minutes with IM). Peak effect 5-15 minutes following IV injection. Duration of the analgesic effect 30-60 minutes (1-2 hours with IM).

Possible adverse effects

  1. Bradycardia (rapid administration)
  2. Respiratory depression
  3. Decrease in physical activity
  4. Physical dependence
  5. Rapid tolerance with prolonged use (>2 days)
  6. Nausea and vomiting
  7. Severe muscle rigidity, especially chest wall rigidity. Can be avoided with slow IV pushes rather than rapid boluses. Have suxamethonium ready

Special considerations

  1. Faster onset of action but shorter duration of action than morphine.
  2. Additive effects with other narcotics and/or other central nervous system depressants.
  3. With prolonged use the minimum effective dose may increase as tolerance develops.
  4. After continuous use, discontinue fentanyl over a few days because physical dependence develops.
  5. Management of fentanyl overdose and/or toxicity: discontinue fentanyl, supportive therapy (ventilation, etc.), naloxone (0.01-0.1 mg/kg/dose IV).

Management of Fentanyl Citrate administration


  • Clear solution 100 micrograms in 2 ml ampoules.
  • 500 micrograms in 10 ml ampoules.
  • Each ml contains sodium hydroxide for pH adjustment. pH 4-7.5.


  • Individual doses are charted on stat page of prescription chart in micrograms/dose.
  • Maintenance doses are charted on the prescription chart in micrograms/dose.

Continuous infusions are charted on fluid chart giving:

  • rate in ml/hour
  • dose in micrograms/kg/hour

Also charted on drug chart under continuous infusions giving:

  • amount of drug to be added
  • base fluid, type and volume
  • micrograms/kg/ml


Slow IV Injection

Administered by nursing staff except the first dose in the nonventilated perioperative neonate.

  1. Administer by slow IV injection over 3-5 minutes. Filter prior to administration through a Pall 0.2 micron filter.
  2. Is compatible with D5W and NS. Compatible with IVN at the Y-site.
  3. Do not mix with other drugs or blood products.
  4. Flush before and after administration of fentanyl with NS.

Slow IV Infusion

  1. Administer by slow IV infusion over 1 hour using a syringe pump. Filter prior to administration through a Pall 0.22 micron filter.
  2. Is compatible with D5W and NS. No data available on dobutamine and dopamine.
  3. Do not mix with other drugs or blood products.
  4. Flush before and after administration of fentanyl with NS.

Continuous Infusion

  1. Dilute prior to administration.
  2. Filter prior to administration through a Pall 0.22 micron filter.
  3. Is compatible with D5W and NS. No data available on dobutamine and dopamine.
  4. Do not mix with other drugs or blood products.
  5. Administer via a syringe pump.
  6. Change fluid and tubing every 24 hours.

Nursing considerations

Warning: Rapid IV injection may result in respiratory paralysis

  1. Baby is managed by a Nurse with neonatal IV drug certification.
  2. Evaluate baby's need for and response to medication.
  3. Assess IV site closely for signs of extravasation.
  4. Assess for signs of adverse reactions.
  5. Continuous cardiorespiratory and blood pressure monitoring.
  6. Monitor oxygen saturations.
  7. Monitor respiratory status carefully. Effect on respiration is longer acting that analgesic effect.
  8. Ensure naloxone and resuscitation equipment is readily available.
  9. Monitor urinary and bladder function.
  10. Drug documentation.
    Record baby's dose out of the narcotic register.
    Record balance discarded out of the narcotic register.
    Two nurses must witness the discarding of the unused drug, syringes and ampoules into the sharps container.
    Two nurses must sign FBC when discarding any unused drugs from a continuous IV infusion.


  • Unopened ampoule - store at room temperature in Narcotic Cupboard.
  • Protect from light.
  • Discard as above once opened.


  1. Collins C, Koren G, Crean P, Klein J, Roy WL, MacLeod SM. Fentanyl pharmacokinetics and haemodynamic effects in preterm infants during ligation of patent ductus arteriosus. Anesth Analg 1985; 64:1078-80.
  2. Koehntop DE, Rodman JH, Brundage DM, Hegland MG, Buckley JJ. Pharmacokinetics of fentanyl in neonates. Anesth Analg 1986; 65:227-35.
  3. Arnold JH, Truog RD, Scavone JM, Fentan T. Changes in the pharmacodynamic response to fentanyl in neonates during continuous infusion. J Pediatr 1991; 119:639-43.
  4. Lane JC, Tennyson MB, Lawless ST, Greenwood RS, Zaritsky AL. Movement disorder after withdrawal of fentanyl infusion. J Pediatr 1991; 119:649-51.
  5. Bergman I, Steeves M, Burckartg, Thompson A. Reversible neurologic abnormalities associated with prolonged intravenous midazolam and fentanyl administration. J Pediatr 1991; 119:644-9.
  6. Nursing 97 Drug Handbook Spinghouse 1997, p357-60.
  7. Barrington KJ, Byrne PJ. Premedication for neonatal intubation. Am J Perinatol. 1998 Apr;15(4):213-6.

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Document Control

  • Date last published: 26 October 2004
  • Document type: Drug Dosage Guideline
  • Services responsible: ADHB Pharmacy, Neonatology
  • Editor: Sarah Bellhouse
  • Review frequency: 2 years