
ALFENTA SHOULD BE ADMINISTERED ONLY BY PERSONS SPECIFICALLY TRAINED IN THE USE OF INTRAVENOUS AND GENERAL ANESTHETIC AGENTS AND IN THE MANAGEMENT OF RESPIRATORY EFFECTS OF POTENT OPIOIDS.
AN OPIOID ANTAGONIST, RESUSCITATIVE AND INTUBATION EQUIPMENT AND OXYGEN SHOULD BE READILY AVAILABLE.
BECAUSE OF THE POSSIBILITY OF DELAYED RESPIRATORY DEPRESSION, MONITORING OF THE PATIENT MUST CONTINUE WELL AFTER SURGERY.
ALFENTA (alfentanil hydrochloride) administered in initial dosages up to 20 mcg/kg may cause skeletal muscle rigidity, particularly of the truncal muscles. The incidence and severity of muscle rigidity is usually dose-related. Administration of ALFENTA at anesthetic induction dosages (above 130 mcg/kg) will consistently produce muscular rigidity with an immediate onset. The onset of muscular rigidity occurs earlier than with other opioids. ALFENTA may produce muscular rigidity that involves all skeletal muscles, including those of the neck and extremities. The incidence may be reduced by: 1) routine methods of administration of neuromuscular blocking agents for balanced opioid anesthesia; 2) administration of up to 1/4 of the full paralyzing dose of a neuromuscular blocking agent just prior to administration of ALFENTA at dosages up to 130 mcg/kg; following loss of consciousness, a full paralyzing dose of a neuromuscular blocking agent should be administered; or 3) simultaneous administration of ALFENTA and a full paralyzing dose of a neuromuscular blocking agent when ALFENTA is used in rapidly administered anesthetic dosages (above 130 mcg/kg).
The neuromuscular blocking agent used should be appropriate for the patient’s cardiovascular status. Adequate facilities should be available for postoperative monitoring and ventilation of patients administered ALFENTA. It is essential that these facilities be fully equipped to handle all degrees of respiratory depression.
PATIENTS RECEIVING MONITORED ANESTHESIA CARE (MAC) SHOULD BE CONTINUOUSLY MONITORED BY PERSONS NOT INVOLVED IN THE CONDUCT OF THE SURGICAL OR DIAGNOSTIC PROCEDURE; OXYGEN SUPPLEMENTATION SHOULD BE IMMEDIATELY AVAILABLE AND PROVIDED WHERE CLINICALLY INDICATED; OXYGEN SATURATION SHOULD BE CONTINUOUSLY MONITORED; THE PATIENT SHOULD BE OBSERVED FOR EARLY SIGNS OF HYPOTENSION, APNEA, UPPER AIRWAY OBSTRUCTION AND/OR OXYGEN DESATURATION.
Severe and unpredictable potentiation of monoamine oxidase (MAO) inhibitors has been reported for other opioid analgesics, and rarely with alfentanil. Therefore when alfentanil is administered to patients who have received MAO inhibitors within 14 days, appropriate monitoring and ready availability of vasodilators and beta-blockers for the treatment of hypertension is recommended.
There is currently no manufacturer warning information available for this drug.
ALFENTA (alfentanil hydrochloride) is indicated:
SEE DOSAGE CHART FOR MORE COMPLETE INFORMATION ON THE USE OF ALFENTA.
ALFENTA (alfentanil hydrochloride) Injection is an opioid analgesic chemically designated as N-[1-[2-(4-ethyl-4,5-dihydro-5-oxo-1H-tetrazol-1-yl)ethyl]-4-(methoxymethyl)-4-piperidinyl]-N-phenylpropanamide monohydrochloride (1:1) with a molecular weight of 452.98 and an n-octanol:water partition coefficient of 128:1 at pH 7.4. The structural formula of ALFENTA is:

ALFENTA is a sterile, non-pyrogenic, preservative free aqueous solution containing alfentanil hydrochloride equivalent to 500 µg per mL of alfentanil base for intravenous injection. The solution, which contains sodium chloride for isotonicity, has a pH range of 4-6. Each mL contains: Active: Alfentanil base 500 mcg. Inactive: Sodium Chloride 9 mg and Water for Injection Q.S.