Fentanyl Citrate Injection

Medical Editor: John P. Cunha, DO, FACOEP Last updated on RxList: 4/21/2022
Fentanyl Citrate Injection Side Effects Center

What Is Fentanyl Citrate Injection?

Fentanyl Citrate Injection, for Intravenous or Intramuscular use is an opioid agonist indicated for analgesic action of short duration during the anesthetic periods, premedication, induction and maintenance, and in the immediate postoperative period (recovery room) as the need arises; use as an opioid analgesic supplement in general or regional anesthesia; administration with a neuroleptic as an anesthetic premedication, for the induction of anesthesia and as an adjunct in the maintenance of general and regional anesthesia; and for use as an anesthetic agent with oxygen in selected high risk patients, such as those undergoing open heart surgery or certain complicated neurological or orthopedic procedures. Fentanyl Citrate Injection is available in generic form.

What Are Side Effects of Fentanyl Citrate Injection?

Common side effects of Fentanyl Citrate Injection include:

Dosage for Fentanyl Citrate Injection

The dose of Fentanyl Citrate Injection is individualize based on the factors such as age, body weight, physical status, underlying pathological condition, use of other drugs, type of anesthesia to be used, and the surgical procedure involved.

What Drugs, Substances, or Supplements Interact with Fentanyl Citrate Injection?

Fentanyl Citrate Injection may interact with macrolide antibiotics, azole antifungals, protease inhibitors, grapefruit juice, rifampin, carbamazepine, phenytoin, other central nervous system (CNS) depressants (such as benzodiazepines and other sedatives/hypnotics, anxiolytics, tranquilizers, muscle relaxants, general anesthetics, antipsychotics, other opioids, alcohol), selective serotonin reuptake inhibitors (SSRIs), serotonin and norepinephrine reuptake inhibitors (SNRIs), tricyclic antidepressants (TCAs), triptans, 5-HT3 receptor antagonists, drugs that effect the serotonin neurotransmitter system, monoamine oxidase (MAO) inhibitors, butorphanol, nalbuphine, pentazocine, buprenorphine, diuretics, anticholinergics, neuroleptics, and nitrous oxide. Tell your doctor all medications and supplements you use. Tell your doctor if you are pregnant or plan to become pregnant before using fentanyl citrate injection.

Fentanyl Citrate Injection During Pregnancy or Breastfeeding

Prolonged use of opioid analgesics such as Fentanyl Citrate during pregnancy may cause neonatal opioid withdrawal syndrome. Fentanyl Citrate passes into breast milk. Withdrawal symptoms can occur in breastfed infants when maternal administration of an opioid analgesic is stopped, or when breastfeeding is stopped. Consult your doctor before breastfeeding. Withdrawal symptoms may occur if you suddenly stop taking Fentanyl Citrate Injection.

Additional Information

Our Fentanyl Citrate Injection, for Intravenous or Intramuscular use Side Effects Drug Center provides a comprehensive view of available drug information on the potential side effects when taking this medication.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.


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Fentanyl Citrate Injection Consumer Information

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Opioid medicine can slow or stop your breathing, and death may occur. A person caring for you should seek emergency medical attention if you have slow breathing with long pauses, blue colored lips, or if you are hard to wake up.

Remove this medicine from your mouth and call your doctor at once if you have:

  • slow heart rate, sighing, shallow breathing, breathing that stops during sleep;
  • severe drowsiness, feeling like you might pass out;
  • dizziness or an upset stomach before the medicine has completely dissolved;
  • confusion, extreme fear, unusual thoughts or behavior; or
  • low cortisol levels--nausea, vomiting, loss of appetite, dizziness, worsening tiredness or weakness.

Seek medical attention right away if you have symptoms of serotonin syndrome, such as: agitation, hallucinations, fever, sweating, shivering, fast heart rate, muscle stiffness, twitching, loss of coordination, nausea, vomiting, or diarrhea.

Serious side effects may be more likely in older adults and those who are overweight, malnourished, or debilitated.

Long-term use of opioid medication may affect fertility (ability to have children) in men or women. It is not known whether opioid effects on fertility are permanent.

Common side effects may include:

  • dizziness, mild drowsiness, depressed mood;
  • sleep problems (insomnia);
  • headache, weakness, anxiety;
  • nausea, vomiting, constipation; or
  • mild rash.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Read the entire detailed patient monograph for Fentanyl Citrate Injection (Fentanyl Citrate Injection)


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Fentanyl Citrate Injection Professional Information


The following serious adverse reactions are described, or described in greater detail, in other sections:

The following adverse reactions associated with the use of fentanyl were identified in clinical studies or postmarketing reports. Because some of these reactions were reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.

As with other opioid agonists, the most common serious adverse reactions reported to occur with fentanyl are respiratory depression, apnea, rigidity, and bradycardia; if these remain untreated, respiratory arrest, circulatory depression or cardiac arrest could occur. Other adverse reactions that have been reported are hypertension, hypotension, dizziness, blurred vision, nausea, emesis, diaphoresis, pruritus, urticarial, laryngospasm, and anaphylaxis.

It has been reported that secondary rebound respiratory depression may occasionally occur postoperatively.

When a tranquilizer is used with fentanyl, the following adverse reactions can occur: chills and/or shivering, restlessness, and postoperative hallucinatory episodes (sometimes associated with transient periods of mental depression); extrapyramidal symptoms (dystonia, akathisia, and oculogyric crisis) have been observed up to 24 hours postoperatively. When they occur, extrapyramidal symptoms can usually be controlled with anti-parkinson agents. Postoperative drowsiness is also frequently reported following the use of neuroleptics with Fentanyl Citrate Injection.

Cases of cardiac dysrhythmias, cardiac arrest, and death have been reported following the use of Fentanyl Citrate Injection with a neuroleptic agent.

Serotonin syndrome: Cases of serotonin syndrome, a potentially life-threatening condition, have been reported during concomitant use of opioids with serotonergic drugs.

Adrenal insufficiency: Cases of adrenal insufficiency have been reported with opioid use, more often following greater than one month of use.

Anaphylaxis: Anaphylaxis has been reported with ingredients contained in Fentanyl Citrate Injection.

Androgen deficiency: Cases of androgen deficiency have occurred with chronic use of opioids [see CLINICAL PHARMACOLOGY].

Read the entire FDA prescribing information for Fentanyl Citrate Injection (Fentanyl Citrate Injection)

© Fentanyl Citrate Injection Patient Information is supplied by Cerner Multum, Inc. and Fentanyl Citrate Injection Consumer information is supplied by First Databank, Inc., used under license and subject to their respective copyrights.

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