Fentanyl (Injection)

Fentanyl (Injection) is used to relieve severe pain during and after surgery. It is also used with other medicines just before or during an operation to help the anesthetic (numbing medicine) work better.

Fentanyl belongs to a group of medicines called narcotic analgesics (pain medicines). It works in the central nervous system (CNS) or brain to relieve pain. Some side effects, like drowsiness or dizziness, are also caused by its actions in the CNS.

This medicine is to be given only by or under the immediate supervision of your doctor.

It is very important for your doctor to monitor you closely while you or your child are receiving this medicine. This will help your doctor see if the medicine is effective and determine if you should keep using it.

This medicine may cause a serious allergic reaction called anaphylaxis. Anaphylaxis can be life-threatening and needs immediate medical attention. Call your doctor right away if you or your child develop a rash, itching, hoarseness, difficulty breathing, trouble swallowing, or any swelling of your hands, face, or mouth while using this medicine.

Do not use more of this medicine or use it more often than your doctor tells you to. This can be life-threatening. Symptoms of an overdose include extreme dizziness or weakness, slow heartbeat or breathing, seizures, trouble breathing, and cold, clammy skin. Call your doctor immediately if you notice these symptoms.

Dizziness, lightheadedness, or fainting may happen with this medicine, especially when standing up suddenly from a lying or sitting position. Getting up slowly may help reduce this issue. Lying down for a while may also help relieve the dizziness or lightheadedness.

This medicine will increase the effects of alcohol and other central nervous system (CNS) depressants. CNS depressants are medicines that slow down the nervous system and may cause drowsiness or less alertness. Examples of CNS depressants include antihistamines or medicines for hay fever, allergies, or colds, sedatives, tranquilizers, or sleeping pills, prescription pain medicine or narcotics, barbiturates or seizure medicines, muscle relaxants, or anesthetics (numbing medicines), including some dental anesthetics. This effect may last for a few days after stopping this medicine. Check with your medical doctor or dentist before taking any of these while you or your child are using this medicine.

This medicine may lead to sleep-related breathing problems (e.g., sleep apnea, sleep-related hypoxemia). Your doctor might reduce your dose if you have sleep apnea (stop breathing for short periods while sleeping) while using this medicine.

This medicine may cause dizziness, drowsiness, confusion, or disorientation. Make sure you know how this medicine affects you before driving, using machines, or doing anything else that could be dangerous if you feel dizzy or are not alert.

This medicine may be habit-forming. If you feel that the medicine is not working as well, do not take more than your prescribed dose. Call your doctor for guidance.

Using narcotics for a long time can lead to severe constipation. To prevent this, your doctor may advise you to take laxatives, drink plenty of fluids, or increase the fiber in your diet. Follow the instructions carefully, as ongoing constipation can lead to more serious issues.

If you have been using this medicine regularly for several weeks or longer, do not change your dose or suddenly stop using it without consulting your doctor. Your doctor may want you to gradually decrease your usage before stopping entirely. This can help prevent worsening of your condition and lower the chance of withdrawal symptoms, such as abdominal or stomach cramps, anxiety, fever, nausea, runny nose, sweating, tremors, or trouble sleeping.

This medicine may increase the risk of muscle rigidity and movement. Inform your doctor if you or your child experience stiff or rigid muscles after using this medicine.

Contact your doctor right away if you have anxiety, restlessness, a fast heartbeat, fever, sweating, muscle spasms, twitching, nausea, vomiting, diarrhea, or if you see or hear things that aren't there. These may be signs of a serious condition called serotonin syndrome. Your risk may be higher if you also take certain other medicines that affect serotonin levels in your body.

Using this medicine during pregnancy may lead to neonatal withdrawal syndrome in your newborn. Notify your doctor immediately if your baby shows signs such as abnormal sleep patterns, diarrhea, a high-pitched cry, irritability, shakiness or tremors, weight loss, vomiting, or failure to gain weight.

Using too much of this medicine may reduce fertility (the ability to have children). Speak with your doctor before using this medicine if you plan to have children.

Do not eat grapefruit or drink grapefruit juice while using this medicine.

Do not take other medicines unless you have discussed them with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

In deciding to use a drug, the risks of taking the medicine must be weighed against the beneficial it will do. This is a decision you and your doctor will make. For this medication, the following should be considered:

Allergies

Inform your clinician if you have ever had any unusual or allergic reaction to this medicine or any other drugs. As well inform your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Pediatric

Appropriate studies have not been performed on the relationship of age to the effects of fentanyl injection in children younger than 2 years of age. Safety and efficacy have not been established.

Geriatric

Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of fentanyl injection in the elderly. Nevertheless, elderly patients are more likely to have age-related lung, kidney, liver, or heart issues, which may require caution and an adjustment in the dose for patients receiving fentanyl injection.

Breast Feeding

There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential chances before taking this medication while breastfeeding.

Interactions with Drugs

Although certain medicines should not be used together at all, in other cases two different drugs may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are receiving this medication, it is especially essential that your healthcare professional know if you are using any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using this drug with any of the following drugs is not recommended. Your physician may decide not to treat you with this drug or change some of the other drugs you take.

• Levoketoconazole
• Mifepristone
• Nalmefene
• Naltrexone
• Safinamide
• Samidorphan

Using this medication with any of the following drugs is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your physician may change the dose or how frequently you use one or both of the drugs.

• Abametapir
• Acepromazine
• Adagrasib
• Alefacept
• Alfentanil
• Almotriptan
• Alprazolam
• Amifampridine
• Amineptine
• Amiodarone
• Amitriptyline
• Amitriptylinoxide
• Amobarbital
• Amoxapine
• Amphetamine
• Amprenavir
• Anileridine
• Aprepitant
• Aripiprazole
• Armodafinil
• Asciminib
• Asenapine
• Atazanavir
• Avacopan
• Baclofen
• Belzutifan
• Benperidol
• Benzhydrocodone
• Benzphetamine
• Berotralstat
• Boceprevir
• Bosentan
• Bromazepam
• Bromopride
• Brompheniramine
• Buprenorphine
• Bupropion
• Buspirone
• Butabarbital
• Butorphanol
• Calcium Oxybate
• Cannabidiol
• Cannabis
• Carbamazepine
• Carbinoxamine
• Cariprazine
• Carisoprodol
• Carphenazine
• Ceritinib
• Cetirizine
• Chloral Hydrate
• Chlordiazepoxide
• Chlorpheniramine
• Chlorpromazine
• Chlorzoxazone
• Ciprofloxacin
• Citalopram
• Clarithromycin
• Clobazam
• Clomipramine
• Clonazepam
• Clopidogrel
• Clorazepate
• Clozapine
• Cobicistat
• Cocaine
• Codeine
• Conivaptan
• Crizotinib
• Cyclobenzaprine
• Cyclosporine
• Dabrafenib
• Daridorexant
• Darunavir
• Delavirdine
• Desipramine
• Desmopressin
• Desvenlafaxine
• Dexamethasone
• Dexmedetomidine
• Dextroamphetamine
• Dextromethorphan
• Dezocine
• Diazepam
• Dibenzepin
• Dichloralphenazone
• Difenoxin
• Dihydrocodeine
• Diltiazem
• Diphenhydramine
• Diphenoxylate
• Dolasetron
• Donepezil
• Doxepin
• Dronedarone
• Droperidol
• Duloxetine
• Efavirenz
• Eletriptan
• Eluxadoline
• Enflurane
• Enzalutamide
• Erdafitinib
• Erythromycin
• Escitalopram
• Esketamine
• Eslicarbazepine Acetate
• Estazolam
• Eszopiclone
• Ethchlorvynol
• Ethopropazine
• Ethylmorphine
• Etravirine
• Fedratinib
• Fenfluramine
• Fexinidazole
• Flibanserin
• Fluconazole
• Fluoxetine
• Fluphenazine
• Flurazepam
• Fluspirilene
• Fluvoxamine
• Fosamprenavir
• Fosaprepitant
• Fosnetupitant
• Fosphenytoin
• Fospropofol
• Frovatriptan
• Furazolidone
• Gabapentin
• Gabapentin Enacarbil
• Gepirone
• Granisetron
• Halazepam
• Haloperidol
• Halothane
• Hexobarbital
• Hydrocodone
• Hydromorphone
• Hydroxyamphetamine
• Hydroxytryptophan
• Hydroxyzine
• Idelalisib
• Imatinib
• Imipramine
• Indinavir
• Iproniazid
• Isocarboxazid
• Isoflurane
• Itraconazole
• Ivacaftor
• Ketamine
• Ketobemidone
• Ketoconazole
• Lacosamide
• Lanreotide
• Lasmiditan
• Lefamulin
• Lemborexant
• Lenacapavir
• Levocetirizine
• Levomilnacipran
• Levorphanol
• Linezolid
• Lisdexamfetamine
• Lithium
• Lofepramine
• Lofexidine
• Lomitapide
• Lopinavir
• Lorazepam
• Lorcaserin
• Lorlatinib
• Loxapine
• Lumacaftor
• Magnesium Oxybate
• Mavacamten
• Meclizine
• Melitracen
• Melperone
• Meperidine
• Mephobarbital
• Meprobamate
• Meptazinol
• Mesoridazine
• Metaxalone
• Methadone
• Methamphetamine
• Methdilazine
• Methocarbamol
• Methohexital
• Methotrimeprazine
• Methylene Blue
• Metoclopramide
• Mibefradil
• Midazolam
• Milnacipran
• Mirtazapine
• Mitotane
• Mobocertinib
• Moclobemide
• Modafinil
• Molindone
• Moricizine
• Morphine
• Morphine Sulfate Liposome
• Nafcillin
• Nalbuphine
• Naratriptan
• Nefazodone
• Nelfinavir
• Netupitant
• Nevirapine
• Nialamide
• Nicardipine
• Nicomorphine
• Nifedipine
• Nilotinib
• Nirmatrelvir
• Nitrazepam
• Nitrous Oxide
• Nortriptyline
• Octreotide
• Olanzapine
• Omaveloxolone
• Ondansetron
• Opipramol
• Opium
• Opium Alkaloids
• Orphenadrine
• Oxazepam
• Oxcarbazepine
• Oxycodone
• Oxymorphone
• Ozanimod
• Palbociclib
• Palonosetron
• Papaveretum
• Paregoric
• Paroxetine
• Pazopanib
• Pentazocine
• Pentobarbital
• Perampanel
• Perazine
• Periciazine
• Perphenazine
• Phenelzine
• Phenobarbital
• Phenytoin
• Pimozide
• Piperacetazine
• Pipotiazine
• Piritramide
• Pirtobrutinib
• Posaconazole
• Potassium Oxybate
• Prazepam
• Prednisone
• Pregabalin
• Primidone
• Procarbazine
• Prochlorperazine
• Promazine
• Promethazine
• Propofol
• Protriptyline
• Quazepam
• Quetiapine
• Ramelteon
• Ranitidine
• Ranolazine
• Rasagiline
• Remifentanil
• Remimazolam
• Remoxipride
• Ribociclib
• Rifabutin
• Rifampin
• Rifapentine
• Ritlecitinib
• Ritonavir
• Rizatriptan
• Ropeginterferon Alfa-2b-njft
• Saquinavir
• Scopolamine
• Secobarbital
• Selegiline
• Selpercatinib
• Sertindole
• Sertraline
• Sibutramine
• Sodium Oxybate
• Sotorasib
• St John's Wort
• Sufentanil
• Sulpiride
• Sumatriptan
• Suvorexant
• Tacrolimus
• Tapentadol
• Taurursodiol
• Telaprevir
• Telithromycin
• Temazepam
• Thiethylperazine
• Thiopental
• Thiopropazate
• Thioridazine
• Tianeptine
• Tilidine
• Tizanidine
• Tocilizumab
• Tolonium Chloride
• Topiramate
• Tramadol
• Tranylcypromine
• Trazodone
• Triazolam
• Trifluoperazine
• Trifluperidol
• Triflupromazine
• Trimeprazine
• Trimipramine
• Trofinetide
• Tryptophan
• Tucatinib
• Venlafaxine
• Verapamil
• Vilazodone
• Voriconazole
• Vortioxetine
• Voxelotor
• Zaleplon
• Ziprasidone
• Zolmitriptan
• Zolpidem
• Zopiclone
• Zotepine
• Zuranolone

Interactions with Food/Tobacco/Alcohol

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain drugs may additionally cause interactions to occur. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using this drug with any of the following is usually not advised, but may be unavoidable in some cases. If used together, your physician may change the dose or how frequently you use this medication, or give you special instructions about the use of food, alcohol, or tobacco.

• Ethanol
• Grapefruit Juice

Other Medical Issues

The presence of other medical problems may affect the use of this medication. Make sure you inform your clinician if you have any other medical issues, especially:

• Adrenal problems or
• Brain tumor, history of or
• Breathing or lung issues (eg, COPD, respiratory depression, sleep apnea) or
• Cor pulmonale (severe heart condition) or
• Drug dependence, especially with narcotics, or history of or
• Head injury, history of or
• Heart disease or
• Hypokalemia (low potassium levels in the blood) or
• Hypomagnesemia (low magnesium levels in the blood)—Use with caution. May raise chance for more serious adverse effects.

• Bradycardia (slow heart rhythm) or
• Gallbladder issues or
• Heart rhythm issues (eg, QT prolongation) or
• Hypertension (high blood pressure) or
• Hypotension (low blood pressure) or
• Pancreatitis (inflammation or swelling of the pancreas) or
• Seizures, history of—Use with caution. May make these conditions worse.

• Kidney disease or
• Liver disease—Use with caution. The effects may be increased since of slower removal of the medication from the body.

Along with its necessary effects, this medicine may cause some unwanted effects. Not all of these side effects will happen, but if they do, they may require medical attention.

Contact your doctor or nurse right away if any of the following side effects occur:

More common

• Chest pain or discomfort
• Difficulty or trouble breathing
• Irregular, fast or slow, or shallow breathing
• Lightheadedness, dizziness, or fainting
• Pale or blue lips, fingernails, or skin
• Severe muscle stiffness
• Slow or irregular heartbeat
• Unusual tiredness

Incidence not known

• Blurred vision
• Change in consciousness
• Chills
• Confusion
• Cough
• Difficulty swallowing
• Fast heartbeat
• Feeling cold
• Headache
• Hives, itching, or skin rash
• Inability to move the eyes
• Inability to sit still
• Increased blinking or eyelid spasms
• Nervousness
• Pounding in the ears
• Puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
• Restlessness
• Seeing, hearing, or feeling things that are not there
• Sticking out the tongue unintentionally
• Sweating
• Tightness in the chest
• Uncontrolled twisting movements of the neck, trunk, arms, or legs
• Unusual facial expressions

Some side effects may happen that typically do not need medical attention. These side effects might go away as your body adjusts to the medicine. Your health care professional may also provide ways to prevent or lessen some of these side effects. Check with your health care professional if any of the following side effects continue, are bothersome, or if you have any questions about them:

Incidence not known

• Bleeding, blistering, burning, coldness, skin discoloration, feeling of pressure, hives, infection, inflammation, itching, lumps, numbness, pain, rash, redness, scarring, soreness, stinging, swelling, tenderness, tingling, ulceration, or warmth at the injection site
• Increased sweating
• Redness of the skin
• Vomiting
• Welts

Other side effects not listed may also occur in some patients. If you notice any other effects, consult your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

In the U.S.

• Sublimaze

Available Dosage Forms:

• Solution

Therapeutic Class: Analgesic

Chemical Class: Opioid

A doctor or other trained health professional will give you or your child this medicine in a hospital. This medicine is given as a shot into a muscle or vein.

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