Fentanyl - Side Effects | Use

This article was medically reviewed by M.Pharm, Marko Tanaskovic on August 12, 2018. To read more about an author, click here.

Fentanyl citrate belongs to opioid analgesics (pain medications), with strong analgesic activity. This medicine is used for cancer pain relief pain. It should not be used to treat mild to moderate pain. This medicine is only available by prescription.


This medication should be avoided in combination with following medications:

  • Isocarboxazid (Marplan)
  • Rasagiline (Azilect)
  • Phenelzine (Nardil)
  • Selegiline (Eldepryl)
  • Furazolidone (Furoxone)
  • Emsam, Zelapar
  • Tranylcypromine (Parnate)

Combination of these medicines with Fentanyl citrate may cause serious side effects.

This medicine should be avoided in patients allergic to fentanyl citrate or other similar medications, such as: hydromorphone, hydrocodone, methadone and others.

It should be taken only under close medical supervision.

Side effects

  • Shallow breathing
  • Bradycardia (slow heartbeat)
  • Fainting
  • Sleepiness
  • Dry mouth
  • Constipation
  • Vomiting
  • Nausea
  • Headache
  • Dizziness

Use with other medicines (Interactions)

  • Calcium-channel blockers, such as:
    • diltiazem and verapamil
  • Antibiotics, such as:
    • clarithromycin
    • telithromycin
    • erythromycin
    • rifampin
    • rifabutin
  • Antifungal medications, such as:
    • fluconazole
    • itraconazole
    • ketoconazole
    • miconazole
    • voriconazole
  • Antiepileptic medicines, such as:
    • carbamazepine
    • oxcarbazepine
    • phenytoin
  • Medicines used to treat AIDS, such as:
    • atazanavir
    • delavirdine
    • efavirenz
    • fosamprenavir
    • indinavir
    • nelfinavir
    • nevirapine
    • ritonavir
    • saquinavir

Tell your doctor if you are experiencing any side effects.

Brand names: Fentora, Onsolis and Actiq.

Information on this website are provided for educational purposes only and are not intended for medical advice, diagnosis or treatment.

If you have any concerns or questions about your health, you should always consult with a physician or other health-care professional.

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