Alfentanil Hydrochloride (2 brand names, 1 dosage form, 1 route)
Available dosage forms: INJECTABLE.
Routes of administration: INJECTION.
Brand Names
- ALFENTA
- ALFENTANIL
Indications and Usage
ALFENTA (alfentanil hydrochloride) is indicated: as an analgesic adjunct given in incremental doses in the maintenance of anesthesia with barbiturate/nitrous oxide/oxygen. as an analgesic administered by continuous infusion with nitrous oxide/oxygen in the maintenance of general anesthesia. as a primary anesthetic agent for the induction of anesthesia in patients undergoing general surgery in which endotracheal intubation and mechanical ventilation are required. as the analgesic component for monitored anesthesia care (MAC).SEE DOSAGE CHART FOR MORE COMPLETE INFORMATION ON THE USE OF ALFENTA.
Dosage and Administration
The dosage of ALFENTA (alfentanil hydrochloride) should be individualized and titrated to the desired effect in each patient according to body weight, physical status, underlying pathological condition, use of other drugs, and type and duration of surgical procedure and anesthesia. In obese patients (more than 20% above ideal total body weight), the dosage of ALFENTA should be determined on the basis of lean body weight. The dose of ALFENTA should be reduced in elderly or debilitated patients (see PRECAUTIONS).Vital signs should be monitored routinely.See Dosage Guidelines for the use of ALFENTA: 1) by incremental injection as an analgesic adjunct to anesthesia with barbiturate/nitrous oxide/oxygen for short surgical procedures (expected duration of less than one hour); 2) by continuous infusion as a maintenance analgesic with nitrous oxide/oxygen for general surgical procedures; and 3) by intravenous injection in anesthetic doses for the induction of anesthesia for general surgical procedures with a minimum expected duration of 45 minutes; and 4) by intravenous injection as the analgesic component for monitored anesthesia care (MAC).DOSAGE GUIDELINES DOSAGE SHOULD BE INDIVIDUALIZED AND TITRATED FOR USE DURING GENERAL ANESTHESIA SPONTANEOUSLY BREATHING/ASSISTED VENTILATIONInduction of Analgesia: 8-20 mcg/kgMaintenance of Analgesia: 3-5 mcg/kg q 5-20 min or 0.5 to 1 mcg/kg/minTotal dose: 8-40 mcg/kg ASSISTED OR CONTROLLED VENTILATION Incremental Injection(To attenuate response to laryngoscopy and intubation)Induction of Analgesia: 20-50 mcg/kgMaintenance of Analgesia: 5-15 mcg/kg q 5-20 minTotal dose: Up to 75 mcg/kg Continuous Infusion(To provide attenuation of response to intubation and incision)Infusion rates are variable and should be titrated to the desired clinical effect.SEE INFUSION DOSAGE GUIDELINES BELOW.Induction of Analgesia: 50-75 mcg/kgMaintenance of Analgesia: 0.5 to 3 mcg/kg/min (Average rate 1 to 1.5 mcg/kg/min)Total dose: Dependent on duration of pr
Contraindications
ALFENTA (alfentanil hydrochloride) is contraindicated in patients with known hypersensitivity to the drug or known intolerance to other opioid agonists.
Adverse Reactions
The most common adverse reactions of opioids are respiratory depression and skeletal muscle rigidity, particularly of the truncal muscles. ALFENTA may produce muscular rigidity that involves the skeletal muscles of the neck and extremities. See CLINICAL PHARMACOLOGY, WARNINGS, and PRECAUTIONS on the management of respiratory depression and skeletal muscle rigidity.The adverse experience profile from 696 patients receiving ALFENTA for Monitored Anesthesia Care (MAC) is similar to the profile established with ALFENTA during general anesthesia. Respiratory events reported during MAC included hypoxia, apnea, and bradypnea. Other adverse events reported by patients receiving ALFENTA for MAC, in order of decreasing frequency, were nausea, hypotension, vomiting, pruritus, confusion, somnolence and agitation.The following adverse reaction information is derived from controlled and open clinical trials in 785 patients who received intravenous ALFENTA during induction and maintenance of general anesthesia. The controlled trials included treatment comparisons with fentanyl, thiopental sodium, enflurane, saline placebo and halothane. The incidence of certain side effects is influenced by the type of use, e.g., chest wall rigidity has a higher reported incidence in clinical trials of alfentanil induction, and by the type of surgery, e.g., nausea and vomiting have a higher reported incidence in patients undergoing gynecologic surgery. The overall reports of nausea and vomiting with ALFENTA were comparable to fentanyl.
Drug Interactions
Both the magnitude and duration of central nervous system and cardiovascular effects may be enhanced when ALFENTA is administered in combination with other CNS depressants such as barbiturates, tranquilizers, opioids, or inhalation general anesthetics. Postoperative respiratory depression may be enhanced or prolonged by these agents. In such cases of combined treatment, the dose of one or both agents should be reduced. Limited clinical experience indicates that requirements for volatile inhalation anesthetics are reduced by 30 to 50% for the first sixty (60) minutes following ALFENTA induction.The concomitant use of erythromycin with ALFENTA can significantly inhibit ALFENTA clearance and may increase the risk of prolonged or delayed respiratory depression.Cimetidine reduces the clearance of ALFENTA. Therefore smaller ALFENTA doses will be required with prolonged administration and the duration of action of ALFENTA may be extended.Perioperative administration of drugs affecting hepatic blood flow or enzyme function may reduce plasma clearance and prolong recovery.
Overdosage
Overdosage would be manifested by extension of the pharmacological actions of ALFENTA (alfentanil hydrochloride) (see CLINICAL PHARMACOLOGY) as with other potent opioid analgesics. No experience of overdosage with ALFENTA was reported during clinical trials. The intravenous LD50 of ALFENTA is 43-51 mg/kg in rats, 72-74 mg/kg in mice, 72-82 mg/kg in guinea pigs and 60-88 mg/kg in dogs. Intravenous administration of an opioid antagonist such as naloxone should be employed as a specific antidote to manage respiratory depression.The duration of respiratory depression following overdosage with ALFENTA may be longer than the duration of action of the opioid antagonist. Administration of an opioid antagonist should not preclude immediate establishment of a patent airway, administration of oxygen, and assisted or controlled ventilation as indicated for hypoventilation or apnea. If respiratory depression is associated with muscular rigidity, a neuromuscular blocking agent may be required to facilitate assisted or controlled ventilation. Intravenous fluids and vasoactive agents may be required to manage hemodynamic instability.