Home > Medical Reference > Encyclopedia (English)

Please install flash player to see this video.

Hospital Virtual Tour

Related Content

Pronunciation:

(al FEN ta nil)

U.S. Brand Names:

Alfenta®

Synonyms:

Alfentanil Hydrochloride

Generic Available:

Yes

Canadian Brand Names:

Alfenta®

Use:

Analgesic adjunct given by continuous infusion or in incremental doses in maintenance of anesthesia with barbiturate or N2O or a primary anesthetic agent for the induction of anesthesia in patients undergoing general surgery in which endotracheal intubation and mechanical ventilation are required

Restrictions:

C-II

Pregnancy Risk Factor:

Contraindications:

Hypersensitivity to alfentanil hydrochloride, to narcotics, or any component of the formulation; increased intracranial pressure, severe respiratory depression

Warnings/Precautions:

Use with caution in patients with drug dependence, head injury, acute asthma and respiratory conditions; hypotension has occurred in neonates with respiratory distress syndrome; use caution when administering to patients with bradyarrhythmias; rapid I.V. infusion may result in skeletal muscle and chest wall rigidity, impaired ventilation, or respiratory distress/arrest; inject slowly over 3-5 minutes. Alfentanil may produce more hypotension compared to fentanyl, therefore, be sure to administer slowly and ensure patient has adequate hydration.

Adverse Reactions:

>10%:

Cardiovascular: Bradycardia, peripheral vasodilation

Central nervous system: Drowsiness, sedation, increased intracranial pressure

Gastrointestinal: Nausea, vomiting, constipation

Endocrine & metabolic: Antidiuretic hormone release

Ocular: Miosis

1% to 10%:

Cardiovascular: Cardiac arrhythmia, orthostatic hypotension

Central nervous system: Confusion, CNS depression

Ocular: Blurred vision

<1%: Convulsions, mental depression, paradoxical CNS excitation or delirium, dizziness, dysesthesia, rash, urticaria, itching, biliary tract spasm, urinary tract spasm, respiratory depression, bronchospasm, laryngospasm, physical and psychological dependence with prolonged use; cold, clammy skin

Overdosage/Toxicology:

Symptoms of overdose include miosis, respiratory depression, seizures, and CNS depression. Naloxone 2 mg I.V. (0.01 mg/kg for children) with repeat administration as necessary up to a total of 10 mg; may precipitate withdrawal.

Drug Interactions:

Substrate of CYP3A4 (major)

Increased effect: Dextroamphetamine may enhance the analgesic effect of morphine and other opiate agonists

Increased toxicity: CNS depressants (eg, benzodiazepines, barbiturates, tricyclic antidepressants), erythromycin, reserpine, beta-blockers

CYP3A4 inhibitors: May increase the levels/effects of alfentanil. Example inhibitors include azole antifungals, ciprofloxacin, clarithromycin, diclofenac, doxycycline, erythromycin, imatinib, isoniazid, nefazodone, nicardipine, propofol, protease inhibitors, quinidine, and verapamil.

Stability:

Dilute in D5W, NS, or LR

Compatibility:

Stable in D5W, NS, D5LR, D5NS

Y-site administration: Compatible: Cisatracurium, etomidate, gatifloxacin, linezolid, propofol, remifentanil. Incompatible: Amphotericin B cholesteryl sulfate complex, thiopental

Compatibility in syringe: Compatible: Atracurium, midazolam, ondansetron

Mechanism of Action:

Binds with stereospecific receptors at many sites within the CNS, increases pain threshold, alters pain perception, inhibits ascending pain pathways; is an ultra short-acting narcotic

Pharmacodynamics/Kinetics:

Onset of action: Rapid

Duration (dose dependent): 30-60 minutes

Distribution: Vd: Newborns, premature: 1 L/kg; Children: 0.163-0.48 L/kg; Adults: 0.46 L/kg

Half-life elimination: Newborns, premature: 5.33-8.75 hours; Children: 40-60 minutes; Adults: 83-97 minutes

Dosage:

Doses should be titrated to appropriate effects; wide range of doses is dependent upon desired degree of analgesia/anesthesia

Children <12 years: Dose not established

Adults: Dose should be based on ideal body weight as follows (see table):

Administration:

Alfentanil

Indication	Approx Duration of Anesthesia (min)	Induction Period (Initial Dose) (mcg/kg)	Maintenance Period (Increments/ Infusion)	Total Dose (mcg/kg)	Effects
Incremental injection	30	8-20	3-5 mcg/kg or 0.5-1 mcg/kg/min	8-40	Spontaneously breathing or assisted ventilation when required.
Incremental injection	30-60	20-50	5-15 mcg/kg	Up to 75	Assisted or controlled ventilation required. Attenuation of response to laryngoscopy and intubation.
Continuous infusion	>45	50-75	0.5-3 mcg/kg/min average infusion rate 1-1.5 mcg/kg/min	Dependent on duration of procedure	Assisted or controlled ventilation required. Some attenuation of response to intubation and incision, with intraoperative stability.
Anesthetic induction	>45	130-245	0.5-1.5 mcg/kg/min or general anesthetic	Dependent on duration of procedure	Assisted or controlled ventilation required. Administer slowly (over 3 minutes). Concentration of inhalation agents reduced by 30% to 50% for initial hour.

Administration:

Administer I.V. slowly over 3-5 minutes or by I.V. continuous infusion.

Monitoring Parameters:

Respiratory rate, blood pressure, heart rate

Reference Range:

100-340 ng/mL (depending upon procedure)

Additional Information:

Alfentanil may produce more muscle rigidity compared to fentanyl, therefore, be sure to administer slowly.

Anesthesia and Critical Care Concerns/Other Considerations:

Alfentanil may produce more muscle rigidity compared to fentanyl, therefore, be sure to administer slowly.

Dental Health: Effects on Dental Treatment:

Key adverse event(s) related to dental treatment: Orthostatic hypotension.

Erythromycin inhibits the liver metabolism of alfentanil resulting in increased sedation and prolonged respiratory depression.

Dental Health: Vasoconstrictor/Local Anesthetic Precautions:

No information available to require special precautions

Mental Health: Effects on Mental Status:

Sedation is common, may see depression or confusion, rarely may cause seizures or delirium

Mental Health: Effects on Psychiatric Treatment:

CNS depressant and beta-blockers may increase toxicity; phenothiazines may antagonize analgesic effect

Dosage Forms:

Injection, solution, as hydrochloride [preservative free]: 500 mcg/mL (2 mL, 5 mL, 10 mL, 20 mL)

International Brand Names:

Alfenta® (CA); Rapifen® (HK, LU, NZ, YU)

References

Bartkowski RR and McDonnell TE, "Prolonged Alfentanil Effect Following Erythromycin Administration,"Anesthesiology, 1990, 73(3):566-8.

Bartkowski RR, Goldberg ME, Larijani GE, et al, "Inhibition of Alfentanil Metabolism by Erythromycin,"Clin Pharmacol Ther, 1989, 46(1):99-102.

Bodenham A and Park GR, "Alfentanil Infusions in Patients Requiring Intensive Care,"Clin Pharmacokinet, 1988, 15(4):216-26.

Davis PJ, Killian A, Stiller RL, et al, "Pharmacokinetics of Alfentanil in Newborn Premature Infants and Older Children,"Dev Pharmacol Ther, 1989, 13(1):21-7.

Kirkham SR and Pugh R, "Opioid Analgesia in Uraemic Patients,"Lancet, 1995, 345(8958):1185.

Marlow N, Weindling AM, Van Peer A, et al, "Alfentanil Pharmacokinetics in Preterm Infants,"Arch Dis Child, 1990, 65(4 Spec No):349-51.

Meistelman C, Saint-Maurice C, Lepaul M, et al, "A Comparison of Alfentanil Pharmacokinetics in Children and Adults,"Anesthesiology, 1987, 66(1):13-6.

Mokhlesi B, Leikin JB, Murray P, et al, "Adult Toxicology in Critical Care: Part II: Specific Poisonings,"Chest, 2003, 123(3):897-922.

Pokela ML, Ryhanen PT, Koivisto ME, et al, "Alfentanil-Induced Rigidity in Newborn Infants,"Anesth Analg, 1992, 75(2):252-7.

Scholz J, Steinfath M, and Schulz M, "Clinical Pharmacokinetics of Alfentanil, Fentanyl, and Sufentanil. An Update,"Clin Pharmacokinet, 1996, 31(4):275-92.

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.