Health Library

Fentanyl (Into the mouth)

Fentanyl (FEN-ta-nil)

Treats pain that is not relieved by other pain medicines. This medicine is an opioid pain reliever.

Brand Name(s):

Abstral, Fentora, Subsys

When This Medicine Should Not Be Used:

How to Use This Medicine:

Thin Sheet, Lozenge, Spray, Tablet, Lollipop

• Take your medicine as directed. Your dose may need to be changed several times to find what works best for you.
• An overdose can be dangerous. Follow directions carefully so you do not get too much medicine at one time. Your doctor may also give you naloxone to treat an overdose.
• Use this medicine only when needed for breakthrough pain. Never use more than your doctor told you to use.
• Use only the brand of medicine your doctor prescribed. Other brands may not work the same way.
• Keep the medicine in the original blister or foil package. Open the package right before you need to use it.
• Abstral® tablets: Place the tablet under your tongue until it dissolves. Do not chew, suck, or swallow the tablet. Do not eat or drink anything until the tablet has dissolved. If your mouth is dry, use water to rinse your mouth before you place the tablet under your tongue.
• Actiq® lozenges: Place the medicine in your mouth between your cheeks and gums and actively suck on the medicine. Use the handle to move the lozenge around your mouth, especially along the inside of your cheeks. Twirl the handle often. Do not bite or chew the lozenge.
• Fentora® tablets: Peel the foil back on the blister pack to remove the tablet. Do not push the tablet through the foil on the blister pack because this may damage the tablet. Do not crush, split, chew, or swallow it. Place the tablet between your upper gum and cheek, above a back molar tooth. You may instead place the tablet under your tongue, on the floor of your mouth. The tablet should dissolve in 14 to 25 minutes. If the tablet does not dissolve completely after 30 minutes, you may drink a glass of water to help you swallow the left over medicine.
• Onsolis® film: Use your tongue to wet the side of your cheek, or rinse your mouth with water in the area where you will place the film. Do not cut or tear the film. Hold the film on a clean, dry finger with the pink side facing up. Press the film against your cheek and hold it there for 5 seconds. Leave the film in place until it dissolves, and do not touch or move the film. Do not chew or swallow the film. Place the second film on the other side of your mouth, if you must use more than one film. Do not eat any food until the film dissolves. You may drink water or other liquids after 5 minutes.
• Subsys® spray: Carefully spray the medicine under your tongue. Hold the medicine under your tongue for 30 to 60 seconds. Do not rinse your mouth and do not spit out any medicine.
• Drink plenty of liquids to help avoid constipation.
• This medicine should come with a Medication Guide. Ask your pharmacist for a copy if you do not have one.
• Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.
• Keep the medicine in the original blister or foil package. Do not use the medicine if the package has been damaged or opened.
• Ask your pharmacist about the best way to dispose of medicine you do not use.
• Actiq® lozenges: Place used handles in the temporary storage bottle from the Actiq® Child Safety Kit. Empty the bottle each day.
• Subsys® spray:
  • Used spray units: Place the used spray unit into the small disposal bag that came with the medicine. Do this right after use. Seal the disposal bag and throw it into a secure trash container, out of the reach of children.
  • Unopened or expired spray units: Hold the unused medicine units upside down, with the nozzle inside the disposal bottle. Spray the units inside the bottle until they are empty. Place all empty spray units into the small bags, and seal them. Shake the bottle from side to side. Place the disposal bottle into the large bag and seal it. Throw all disposal bags into a secure trash container, out of the reach of children.

Drugs and Foods to Avoid:

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

• Do not use this medicine if you are using or have used an MAO inhibitor within the past 14 days.
• Some medicines can affect how fentanyl works. Tell your doctor if you are using any of the following:
  • Carbamazepine, erythromycin, ketoconazole, mirtazapine, phenytoin, rifampin, ritonavir, tramadol, or trazodone
  • Blood pressure medicine
  • Diuretic (water pill)
  • Medicine to treat depression
  • Phenothiazine medicine
• Do not drink alcohol while you are using this medicine.
• Tell your doctor if you use anything else that makes you sleepy. Some examples are allergy medicine, narcotic pain medicine, and alcohol. Tell your doctor if you are also using buprenorphine, butorphanol, nalbuphine, pentazocine, a benzodiazepine, or a muscle relaxer.

Warnings While Using This Medicine:

• Tell your doctor if you are pregnant or breastfeeding, or if you have kidney disease, liver disease, lung or breathing problems (including COPD, apnea), mucositis (sores in your mouth), adrenal problems, gallbladder or pancreas problems, seizures, or a slow heart rate. Tell your doctor if you have had a head injury or brain surgery, or a history of drug or alcohol use disorder.
• This medicine may cause the following problems:
  • High risk of overdose, which can lead to death
  • Respiratory depression (serious breathing problem that can be life-threatening)
  • Sleep-related breathing problems (including sleep apnea, sleep-related hypoxemia)
  • Worsening of pain
  • Serotonin syndrome, when used with certain medicines
  • Adrenal gland problems
  • Low blood pressure
  • Seizures
• This medicine may make you dizzy or drowsy. Do not drive or do anything else that could be dangerous until you know how this medicine affects you. Sit or lie down if you feel dizzy. Stand up carefully.
• This medicine can cause serious harm or death to a child. Always keep this medicine out of the reach of children. Carefully and properly dispose of both used units and medicine that has not been used.
• Actiq® contains 2 grams of sugar in each unit. Schedule regular dentist visits. Be careful if you need to keep track of your sugar intake.
• This medicine can be habit-forming. Do not use more than your prescribed dose. Call your doctor if you think your medicine is not working.
• Do not stop using this medicine suddenly. Your doctor will need to slowly decrease your dose before you stop it completely.
• This medicine could cause infertility. Talk with your doctor before using this medicine if you plan to have children.
• This medicine may cause constipation, especially with long-term use. Ask your doctor if you should use a laxative to prevent and treat constipation.
• Keep all medicine out of the reach of children. Never share your medicine with anyone.

Possible Side Effects While Using This Medicine:

Call your doctor right away if you notice any of these side effects:

• Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
• Anxiety, restlessness, fast heartbeat, fever, sweating, muscle spasms, twitching, nausea, vomiting, diarrhea, seeing or hearing things that are not there
• Blue lips, fingernails, or skin
• Chest pain or tightness
• Decrease in how much or how often you urinate
• Extreme dizziness or weakness, shallow breathing, slow or uneven heartbeat, sweating, cold or clammy skin, seizures
• Severe confusion, lightheadedness, dizziness, fainting
• Severe constipation, stomach pain, or vomiting
• Worsening of pain, increased sensitivity to pain

If you notice these less serious side effects, talk with your doctor:

• Dry mouth, unusual or bitter taste
• Headache
• Mild constipation, diarrhea, nausea, vomiting
• Sores or white patches on your lips, mouth, or throat

If you notice other side effects that you think are caused by this medicine, tell your doctor

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

Last Updated: 9/6/2024