Alfentanil

Alfentanil is a potent short-acting opioid used in anesthesia. Alfentanil may be used alone or with other medications.

• Alfentanil is available under the following different brand names: Alfenta, Rapifen 

Common side effects of Alfentanil include:

• Drowsiness,
• Sleepiness, and
• False sense of well-being

Serious side effects of Alfentanil include:

• Hives,
• Difficulty breathing,
• Swelling of the face, lips, tongue, or throat,
• Blurred vision,
• Chest pain or discomfort,
• Dizziness,
• Confusion,
• Fainting,
• Lightheadedness,
• Slow, fast, pounding, or irregular heartbeat,
• Headache,
• Slow, rapid, or shallow breathing,
• Nervousness,
• Breathing that stops,
• Pale or blue lips, fingernails, or skin,
• Pounding in the ears,
• Sweating,
• Tiredness,
• Weakness,
• Cough,
• Noisy breathing,
• Rigid (very stiff) muscles,
• Tightness in the chest,
• Agitation,
• Darkening of the skin,
• Diarrhoea,
• Trouble swallowing,
• Fever,
• Hives,
• Skin rash,
• Loss of appetite,
• Nausea,
• Overactive reflexes,
• Poor coordination,
• Puffiness or swelling of the eyelids,
• Restlessness,
• Shivering,
• Sweating,
• Talking or acting with excitement,
• Trembling or shaking,
• Twitching, and
• Vomiting

Rare side effects of Alfentanil include:

• none 

Seek medical care or call 911 at once if you have the following serious side effects:

• Severe headache, confusion, slurred speech, arm or leg weakness, trouble walking, loss of coordination, feeling unsteady, very stiff muscles, high fever, profuse sweating, or tremors;
• Serious eye symptoms such as sudden vision loss, blurred vision, tunnel vision, eye pain or swelling, or seeing halos around lights;
• Serious heart symptoms include fast, irregular, or pounding heartbeats; fluttering in the chest; shortness of breath; sudden dizziness, lightheadedness, or passing out.

This is not a complete list of side effects and other serious side effects or health problems that may occur because of the use of this drug. Call your doctor for medical advice about serious side effects or adverse reactions. You may report side effects or health problems to FDA at 1-800-FDA-1088.

Adult and pediatric dosage

Injectable solution: Schedule II

• 0.5 mg/mL

Incremental Injection: Anesthesia below 30 Minutes

Adult dosage

• Induction: 8-20 mcg/kg Intravenous  
• Maintenance: 3-5 mcg/kg Intravenous increments every 5-20min, or 0.5-1 mcg/kg/min Intravenous
• Total dose: 8-40 mcg/kg Intravenous
• Incremental Injection: Anesthesia 30-60 Minutes

Adult dosage

• Induction: 20-50 mcg/kg Intravenous
• Maintenance: 5-15 mcg/kg Intravenous increments every 5-20min
• Total dose: Up to 75 mcg/kg Intravenous
• Anesthetic Induction: Anesthesia above 45 Minutes

Adult dosage

• Induction: 130-245 mcg/kg Intravenous 
• Maintenance: 0.5-1.5 mcg/kg/min Intravenous or another general anesthetic
• Total dose: depends on the duration of operation
• Continuous Infusion: For Anesthesia above 45 Minutes

Adult dosage

• Induction: 50-75 mcg/kg Intravenous
• Maintenance: 0.5-3 mcg/kg/min Intravenous
• Total dose: depends on the duration of operation

Dosage Considerations – Should be Given as Follows: 

• See “Dosages”

If your medical doctor is using this medicine to treat your pain, your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor, health care provider, or pharmacist first.

• Alfentanil has severe interactions with the following drug:
  • Alvimopan
• Alfentanil has serious interactions with at least 53 other drugs.
• Alfentanil has moderate interactions with at least 233 other drugs.
• Alfentanil has minor interactions with at least 58 other drugs.

This information does not contain all possible interactions or adverse effects. Visit the RxList Drug Interaction Checker for any drug interactions. Therefore, before using this product, tell your doctor or pharmacist about all your products. Keep a list of all your medications with you and share this information with your doctor and pharmacist. Check with your healthcare professional or doctor for additional medical advice, or if you have health questions or concerns.

Contraindications

• Hypersensitivity
• Increased intracranial pressure
• Severe respiratory depression 

Effects of drug abuse

• None

Short-Term Effects

• See “What Are Side Effects Associated with Using Alfentanil?”

Long-Term Effects

• See “What Are Side Effects Associated with Using Alfentanil?”

Cautions

• Use caution in bradycardia, compromised cardiac reserve, head injury, hypothyroidism, increased ICP, intracranial lesions, renal impairment, respiratory impairment, obesity, history of drug abuse
• Concurrent administration of benzodiazepine or neuromuscular blocker will decrease chest wall rigidity
• Should be administered by trained individuals
• In patients who may be susceptible to intracranial effects of CO2 retention (.g., those with evidence of increased intracranial pressure or brain tumors), therapy may reduce respiratory drive, and resultant CO2 retention can further increase intracranial pressure; monitor such patients for signs of sedation and respiratory depression, particularly when initiating therapy; opioids may obscure the clinical course in a patient with a head injury; avoid the use in patients with impaired consciousness or coma
• May cause spasm of the sphincter of Oddi; opioids may cause increases in serum amylase; monitor patients with biliary tract disease, including acute pancreatitis, for worsening symptoms
• Therapy may increase the frequency of seizures in patients with seizure disorders and other clinical settings associated with seizures; monitor patients for worsened seizure control during therapy
• Life-threatening respiratory depression is more likely to occur in elderly, cachectic, or debilitated patients because they may have altered pharmacokinetics or altered clearance compared to younger, healthier patients; monitor closely
• Profound sedation, respiratory depression, coma, and death may result from concomitant administration with benzodiazepines or other CNS depressants (. g., non-benzodiazepine sedatives/hypnotics, anxiolytics, tranquilizers, muscle relaxants, general anesthetics, antipsychotics, other opioids, alcohol); because of these risks, reserve concomitant prescribing of these drugs for use in patients for whom alternative treatment options are inadequate
• Opioids can cause sleep-related breathing disorders including central sleep apnea (CSA) and sleep-related hypoxemia; opioid use increases the risk of CSA in a dose-dependent fashion; in patients who present with CSA, consider decreasing opioid dosage using best practices for opioid taper
• Cases of serotonin syndrome, a potentially life-threatening condition, reported with concomitant use of serotonergic drugs; this may occur within the recommended dosage range; the onset of symptoms generally occurs within several hours to a few days of concomitant use, but may occur later than that; discontinue therapy immediately if serotonin syndrome is suspected
• Muscle rigidity occurring during induction of can be treated by decreasing the rate or discontinuing the infusion of the drug or by administering a neuromuscular blocking agent; neuromuscular blocking agents used should be compatible with the patient's cardiovascular status
• Not to be administered into the same IV tubing with blood due to potential inactivation by nonspecific esterases in blood products
• Proper placement of needle or catheter in epidural space should be verified before the drug is injected to assure that unintentional intravascular or intrathecal administration does not occur; unintentional intravascular injection of sufentanil could result in a potentially serious overdose, including acute truncal muscular rigidity and apnea; unintentional intrathecal injection of sufentanil/bupivacaine epidural doses and volume could produce effects of high spinal anesthesia including prolonged paralysis and delayed recovery; if analgesia is inadequate, placement and integrity of catheter should be verified before administration of any additional epidural medications; administer epidurally by slow injection
• Bradycardia may occur; monitor heart rate during dosage initiation and titration; responsive to ephedrine or anticholinergic drugs
• Therapy may cause severe hypotension including orthostatic hypotension and syncope in ambulatory patients; there is increased risk in patients whose ability to maintain blood pressure has already been compromised by a reduced blood volume or concurrent administration of certain CNS depressant drugs (.g., phenothiazines or general anesthetics); monitor patients for signs of hypotension after initiating or titrating dosage; in patients with circulatory shock, therapy may cause vasodilation that can further reduce cardiac output and blood pressure; avoid therapy in patients with circulatory shock

Pregnancy and Lactation

• Prolonged use of opioid analgesics during pregnancy may cause neonatal opioid withdrawal syndrome; available data in pregnant women are insufficient to inform a drug-associated risk for major birth defects and miscarriage
• Labor or delivery
  • Opioids cross the placenta and may produce respiratory depression and psycho-physiologic effects in neonates; an opioid antagonist, such as naloxone, must be available for reversal of opioid-induced respiratory depression in the neonates; the drug is not recommended for use in women during and immediately before labor when the use of shorter-acting analgesics or other analgesic techniques are more appropriate; opioid analgesics can prolong labor through actions that temporarily reduce strength, duration, and frequency of uterine contractions; however, this effect is not consistent and may be offset by an increased rate of cervical dilatation, which tends to shorten labor; monitor neonates exposed to opioid analgesics during labor for signs of excess sedation and respiratory depression
• Lactation
  • The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for therapy; capsules and any potential adverse effects on the breastfed infant from therapy or underlying maternal condition
  • Monitor infants exposed to the drug through breast milk for excess sedation and respiratory depression; withdrawal symptoms can occur in breastfed infants when maternal administration of an opioid analgesic is stopped, or when breastfeeding is stopped
  • Withdrawal signs can occur in breastfed infants when maternal administration of an opioid analgesic is stopped or when breastfeeding is stopped; naloxone may precipitate opioid withdrawal in a breast-fed infant whose mother received opioid analgesics
  • Lactation: use with caution