Alfentanil

U.S. BRAND NAMES — Alfenta®
PHARMACOLOGIC CATEGORY Analgesic, Opioid
DOSING: ADULTS — Doses should be titrated to appropriate effects; wide range of doses is dependent upon desired degree of analgesia/anesthesia
Anesthesia: I.V.: Dose should be based on ideal body weight as follows (see table).
Adult Dosage Adjustments
Incremental injection in anesthesia 30 minutes: Initial dose (induction period): 8-20 mcg/kg Maintenance period (increments/infusion): 3-5 mcg/kg or 0.5-1 mcg/kg/minute Total dose: 8-40 mcg/kg Appropriate effects: Spontaneously breathing or assisted ventilation when required
Incremental injection in anesthesia of 30-60 minutes: Initial dose (induction period): 20-50 mcg/kg Maintenance period (increments/infusion): 5-15 mcg/kg Total dose: Up to 75 mcg/kg Appropriate effects: Assisted or controlled ventilation required. Attenuation of response to laryngoscopy and intubation.
Continuous infusion >45 minutes: Initial dose (induction period): 50-75 mcg/kg Maintenance period (increments/infusion): 0.5-3 mcg/kg/minute; average infusion rate: 1-1.5 mcg/kg/minute Total dose: Dependent on duration of procedure Appropriate effects: Assisted or controlled ventilation required. Some attenuation of response to intubation and incision, with intraoperative stability.
Anesthetic induction >45 minutes: Initial dose (induction period): 130-245 mcg/kg Maintenance period (increments/infusion): 0.5-1.5 mcg/kg/minute or general anesthetic Total dose: Dependent on duration of procedure Appropriate effects: Assisted or controlled ventilation required. Administer slowly (over 3 minutes). Concentration of inhalation agents reduced by 30% to 50% for initial hour.
DOSING: PEDIATRIC
(For additional information see "Alfentanil: Pediatric drug information")Children <12 years: Dose has not been established.
Children 12 years: Refer to adult dosing.
DOSING: ELDERLY — Refer to adult dosing.
DOSAGE FORMS — Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Injection, solution [preservative free]: 500 mcg/mL (2 mL, 5 mL, 10 mL) Alfenta®: 500 mcg/mL (2 mL, 5 mL, 10 mL, 20 mL)
DOSAGE FORMS: CONCISE Injection, solution [preservative free]: 500 mcg/mL (2 mL, 5 mL, 10 mL) Alfenta®: 500 mcg/mL (2 mL, 5 mL, 10 mL, 20 mL)
GENERIC EQUIVALENT AVAILABLE — Yes
ADMINISTRATION — Administer I.V. slowly over 3-5 minutes or by I.V. continuous infusion.
COMPATIBILITY — Stable in D5W, NS, LR, 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.
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
ADVERSE REACTIONS SIGNIFICANT >10%: Cardiovascular: Bradycardia, peripheral vasodilation Central nervous system: Drowsiness, sedation, intracranial pressure increased Endocrine & metabolic: Antidiuretic hormone release Gastrointestinal: Nausea, vomiting, constipation Ocular: Miosis
1% to 10%: Cardiovascular: Cardiac arrhythmia, orthostatic hypotension Central nervous system: Confusion, CNS depression Ocular: Blurred vision
<1% (Limited to important or life-threatening): 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
CONTRAINDICATIONS — Hypersensitivity to alfentanil hydrochloride, to narcotics, or any component of the formulation; increased intracranial pressure, severe respiratory depression
WARNINGS / PRECAUTIONS Concerns related to adverse effects: Hypotension: May cause hypotension; use with caution in patients with hypovolemia, cardiovascular disease (including acute MI), or drugs which may exaggerate hypotensive effects (including phenothiazines or general anesthetics). Opioid agonist toxicities: Shares the toxic potentials of opiate agonists, and precautions of opiate agonist therapy should be observed.
Disease-related concerns: Bradyarrhythmias: Use with caution when administering to patients with bradyarrhythmias. Drug abuse: Use with caution in patients with a history of drug abuse or acute alcoholism; potential for drug dependency exists. Tolerance, psychological and physical dependence may occur with prolonged use. Head trauma: Use with extreme caution in patients with head injury, intracranial lesions, or elevated intracranial pressure; exaggerated elevation of ICP may occur. Obesity: Use with caution in patients who are morbidly obese. Respiratory disease: Use with caution in patients with pre-existing respiratory compromise (hypoxia and/or hypercapnia), COPD or other obstructive pulmonary disease, and kyphoscoliosis or other skeletal disorder which may alter respiratory function.
Special populations: Neonates: Hypotension has occurred in neonates with respiratory distress syndrome. Pediatrics: Safety and efficacy have not been established in children <12 years old.
Other warnings/precautions: Rapid infusion: Inject slowly over 3-5 minutes; rapid I.V. infusion may result in skeletal muscle and chest wall rigidity, impaired ventilation, or respiratory distress/arrest; nondepolarizing skeletal muscle relaxant may be required. Trained individuals: Due to the high incidence of apnea, hypotension, tachycardia and muscle rigidity; it should be administered by individuals specifically trained in the use of anesthetic agents and should not be used in diagnostic or therapeutic procedures outside the monitored anesthesia setting; resuscitative and intubation equipment should be readily available.
RESTRICTIONS — C-II
DRUG INTERACTIONS — Substrate of CYP3A4 (major)
Dextroamphetamine: May enhance the analgesic effect of morphine and other opiate agonists.
Increased toxicity with 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, clarithromycin, diclofenac, doxycycline, erythromycin, imatinib, isoniazid, nefazodone, nicardipine, propofol, protease inhibitors, quinidine, telithromycin, and verapamil.
PREGNANCY RISK FACTOR — C (show table)
MONITORING PARAMETERS — Respiratory rate, blood pressure, heart rate
REFERENCE RANGE — 100-340 ng/mL (depending upon procedure)
TOXICOLOGY / OVERDOSE COMPREHENSIVE — Symptoms include miosis, respiratory depression, seizures, and CNS depression. Treatment includes 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.
CANADIAN BRAND NAMES — Alfentanil Injection, USP; Alfenta®
INTERNATIONAL BRAND NAMES — Alfenil (KR); Alfenta (BR, CA); Alfentanil Injection, USP (CA); Brevafen (AR); Fanaxal (ES); Fentalim (IT); Rapifen (AE, AT, AU, BE, BG, BH, BR, CH, CL, CY, CZ, DE, DK, EG, FI, FR, GB, GR, HK, HR, HU, IE, IL, IQ, IR, IT, JO, KW, LB, LY, NL, NO, NZ, OM, PL, PT, PY, QA, RU, SA, SE, SY, TW, UY, VE, YE, ZA)
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