Alfentanil Side Effects

Medically reviewed by Drugs.com. Last updated on Dec 12, 2024.

Applies to alfentanil: intravenous solution.

Important warnings This medicine can cause some serious health issues

Intravenous route (solution)

Alfentanil HCl injection exposes users to risks of addiction, abuse, and misuse, which can lead to overdose and death.

Assess patient’s risk before prescribing and monitor regularly for these behaviors and conditions.

Serious side effects of alfentanil

Along with its needed effects, alfentanil may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor or nurse immediately if any of the following side effects occur while taking alfentanil:

More common side effects

• blurred vision
• chest pain or discomfort
• confusion
• difficult or troubled breathing
• dizziness
• dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
• fainting
• fast, slow, pounding, or irregular heartbeat or pulse
• headache
• irregular, fast or slow, or shallow breathing
• lightheadedness, dizziness, or fainting
• nervousness
• not breathing
• pale or blue lips, fingernails, or skin
• pounding in the ears
• sweating
• trouble breathing
• unusual tiredness or weakness

Rare side effects

• cough
• noisy breathing
• rigid muscles of the neck, arms, and legs
• tightness in the chest

Incidence not known

• agitation
• cough
• darkening of the skin
• diarrhea
• difficulty with swallowing
• fainting
• fever
• hives, itching, or skin rash
• loss of appetite
• nausea
• overactive reflexes
• poor coordination
• puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
• restlessness
• shivering
• sweating
• talking or acting with excitement you cannot control
• trembling or shaking
• twitching
• vomiting

Other side effects of alfentanil

Some side effects of alfentanil may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common side effects

• drowsiness
• sleepiness

Rare side effects

• false or unusual sense of well-being

For healthcare professionals

Applies to alfentanil: injectable solution.

General adverse events

The most commonly reported adverse reactions include apnea, rigidity, and bradycardia.^[Ref]

Respiratory

• Common (1% to 10%): Apnea
• Uncommon (0.1% to 1%): Hypercarbia, laryngospasm
• Frequency not reported: Life-threatening respiratory depression, postoperative respiratory depression, bronchospasm, hypoxia, bradypnea, hiccups, hypercapnia, epistaxis, airway complication of anesthesia, endotracheal intubation complication
• Postmarketing reports: Respiratory arrest, cough^[Ref]

Hypersensitivity

• Postmarketing reports: Anaphylaxis^[Ref]

Cardiovascular

• Very common (10% or more): Arrhythmia, bradycardia (14%), hypertension (18%), hypotension (18%), tachycardia (12%)
• Frequency not reported: Asystole
• Postmarketing reports: Cardiac arrest^[Ref]

Musculoskeletal

• Very common (10% or more): Chest wall rigidity (17%),
• Common (1% to 10%): Skeletal muscle movements, muscle rigidity
• Uncommon (0.1% to 1%): Skeletal muscle rigidity of neck and extremities^[Ref]

Nervous system

• Common (1% to 10%): Dizziness, movement disorders, dyskinesia
• Uncommon (0.1% to 1%): Headache
• Frequency not reported: Serotonin syndrome, seizures, sleepiness/postoperative sedation, somnolence, neurological anesthetic complication
• Postmarketing reports: Myoclonic movements^[Ref]

Psychiatric

• Common (1% to 10%): Euphoric mood
• Uncommon (0.1% to 1%): Postoperative confusion, postoperative euphoria, excitation
• Frequency not reported: Addiction abuse, misuse, agitation, crying
• Postmarketing reports: Disorientation^[Ref]

Gastrointestinal

• Very common (10% or more): Nausea (28%), vomiting (18%)^[Ref]

Dermatologic

• Uncommon (0.1% to 1%): Itching, urticaria
• Frequency not reported: Pruritus, allergic dermatitis, hyperhidrosis
• Postmarketing reports: Erythema, rash^[Ref]

Local

• Common (1% to 10%): Injection site pain^[Ref]

Endocrine

Opioids:

• Postmarketing reports: Adrenal insufficiency, androgen deficiency^[Ref]

Adrenal insufficiency has been reported with opioid use, more often following greater than 1 month of use. Androgen deficiency has occurred with chronic use of opioids.^[Ref]

Genitourinary

• Uncommon (0.1% to 1%): Urinary retention^[Ref]

Ocular

• Common (1% to 10%): Visual disturbance
• Frequency not reported: Blurred vision
• Postmarketing reports: Miosis^[Ref]

Other

• Common (1% to 10%): Fatigue, chills
• Uncommon (0.1% to 1%): Shivering
• Postmarketing reports: Pyrexia^[Ref]

Further information

Alfentanil side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Note: Medication side effects may be underreported. If you are experiencing side effects that are not listed, submit a report to the FDA by following this guide.

Medical Disclaimer