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Subsys

fentanyl
Used for Pain
Used for Pain

Subsys (fentanyl) is a strong opioid medication that's used to relieve breakthrough pain in adults with cancer who already take around-the-clock opioid pain medications. Subsys (fentanyl) is sprayed under the tongue. Side effects include nausea, constipation, and sleepiness. It also has a risk for slowed breathing and misuse.

Please note: Subsys (fentanyl) has been discontinued and is no longer available in the United States. Talk to your provider about alternative options to treat your pain.

Last reviewed on January 4, 2024
Subsys (fentanyl) is a controlled substance, which means that it's more likely to be misused or cause dependence. There are federal and state laws that limit the amount of medication that can be prescribed or dispensed within a certain period of time.
basics-icon

What is Subsys (fentanyl)?

What is Subsys (fentanyl) used for?

  • Breakthrough cancer pain in adults 18 years and older

How Subsys (fentanyl) works

Subsys (fentanyl) is an opioid. It attaches to certain mu-opioid receptors in your brain to lower how much pain you feel.

Drug Facts

Common BrandsSubsys (brand no longer available)
Drug ClassOpioid
Controlled Substance ClassificationSchedule II
Generic StatusNo lower-cost generic available
AvailabilityDiscontinued
warings-icon

What are the risks and warnings for Subsys (fentanyl)?

Subsys (fentanyl) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.

risk-warning

Potential for addiction and misuse

  • Risk factors: Personal or family history of alcohol or substance use disorder | Personal or family history of mental health problems

    Subsys (fentanyl) is a controlled substance that has a risk for addiction and misuse. Take the medication exactly as prescribed. Don't change the dose or how often you take it without talking to your provider first.

    Misusing Subsys (fentanyl) might cause it to work less well. It can also raise the risk for serious and possibly life-threatening side effects, such as dangerously slow breathing, inability to stay awake, and opioid overdose. Your healthcare provider will prescribe the lowest amount of Subsys (fentanyl) that's necessary to manage your pain for the shortest period of time possible.

    Because of the risk for misuse, addiction, and overdose, Subsys (fentanyl) is included in the Risk Evaluation and Mitigation Strategy (REMS) program called the Transmucosal Immediate Release Fentanyl (TIRF) REMS program. Healthcare providers and pharmacies must register with the program, receive training on proper medication use, and discuss safe medication use with you.

    risk-warning

    Dangerously slow breathing (respiratory depression)

    • Risk factors: Taking medications that can cause slow breathing | Drinking alcohol | Older age | Being frail | Medical conditions that cause breathing problems (e.g., COPD, asthma, head injury) | Taking too much Subsys (fentanyl)

      Opioids like Subsys (fentanyl) can cause dangerously slow breathing, which can be life-threatening. This can happen to anyone at recommended doses. But the risk is greatest when you first start treatment or if your dose goes up.

      Don't take an opioid with alcohol or other medications that slow your body down (e.g., benzodiazepines, other opioids, muscle relaxants). Doing so raises your risk of extremely slowed breathing.

      Your provider might prescribe naloxone (Narcan), a medication that can reverse slowed breathing from opioids. Carry it with you at all times in case you have breathing problems from the opioid medication. If you or your loved one notices that you have trouble breathing or bluish-colored lips, fingers, or toes, use naloxone if you have it and call 911 to get medical help right away.

      risk-warning

      Opioid overdose

      • Risk factors: History of opioid use disorder | Previous opioid overdose | Taking high doses of Subsys (fentanyl) | Taking more opioids than prescribed | Alcohol use


        Take opioid medications exactly as prescribed. Taking too much or taking it more often than prescribed can lead to an overdose. In addition, it can be especially dangerous if a child accidentally ingests opioid medications, such as Subsys (fentanyl). Store your medication out of reach from children, pets, or visitors to prevent accidental exposure or overdose.

        Symptoms of an opioid overdose include not responding to sound or touch, extremely slowed breathing, extreme sleepiness, slow heartbeat, and cold or clammy skin. Be sure you and your loved ones know how to recognize an overdose. Your provider will probably prescribe naloxone (Narcan), a medication that can treat an opioid overdose. Carry naloxone with you at all times in case an overdose happens, and call 911 right away if this happens.

        risk-warning

        Difficulty concentrating and extreme sleepiness

        • Risk factors: Taking high doses of Subsys (fentanyl) | Age 65 years or older | Drinking alcohol | Taking other medications that can cause sleepiness

          Opioids can cause extreme sleepiness and lower your ability to think, react, and focus. Don't drink alcohol or take other medications that can cause sleepiness or "brain fog" (e.g., benzodiazepines, muscle relaxants, sleep medications) with Subsys (fentanyl). Doing so can worsen these side effects. Make sure you know how your opioid medication affects you before driving a car or doing activities that require your concentration. Talk to your healthcare provider right away if you feel too sleepy from taking Subsys (fentanyl).

          risk-warning

          Harm to newborn babies

          Long-term use of opioids during pregnancy can cause your unborn baby to become dependent on the medication. This is because the opioid (fentanyl) can pass through the placenta to your unborn baby. Once your baby is born, they can experience withdrawal symptoms, such as high-pitched crying, poor feeding and sucking behavior, trembling, abnormal sleep patterns, and seizures. This condition is called neonatal opioid withdrawal syndrome and can be life-threatening if not recognized and treated in time. Let your healthcare provider know if you've used Subsys (fentanyl) or other opioids during pregnancy or if you notice these symptoms in your baby.

          risk-warning

          Drug interactions

          Tell your providers about all of the medications you're taking or planning to take with opioids like Subsys (fentanyl). Taking certain medications with opioids or changing your medication routine can raise your risk for dangerous side effects. Benzodiazepines, sedatives, and alcohol can worsen opioid side effects like slow breathing or severe sleepiness and can be life-threatening. In addition, taking opioids like Subsys (fentanyl) with certain antidepressants can also raise your risk of serotonin syndrome, a rare but serious side effect that can lead to fast heart rate, sweating, and muscle problems.

          risk-warning

          Physical dependence and withdrawal

          • Risk factors: Long-term use of Subsys (fentanyl)

            Opioids like Subsys (fentanyl) can cause physical dependence when they're taken for a long time. This means that your body relies on the medication to function. You might experience withdrawal if you stop taking the medication suddenly or lower your dose too fast.

            Withdrawal symptoms include anxiety, restlessness, irritability, sweating, and chills. Don't lower your dose or stop taking the medication suddenly without talking to your healthcare provider first. Your provider will slowly lower your dose to prevent withdrawal symptoms. Talk to your provider about alternative pain medications if you have concerns about the risk for dependence and withdrawal from opioid use.

            risk-warning

            Low blood pressure

            Subsys (fentanyl) and other opioids can cause extremely low blood pressure. Your blood pressure might drop suddenly when you stand from a sitting or lying down position. This can lead to dizziness and fainting. To avoid falling, get up slowly if you've been sitting or lying down. Talk to your healthcare provider if dizziness or lightheadedness doesn't go away.

            risk-warning

            Low adrenal hormone levels

            • Risk factors: Taking Subsys (fentanyl) for longer than 1 month

              Some people taking opioids like Subsys (fentanyl) had low adrenal hormone levels. This might be more likely to happen after taking opioids for longer than 1 month. Symptoms include tiredness, dizziness, weakness, not feeling hungry, nausea, and vomiting. Let your provider know if you have these symptoms. If your adrenal hormone levels are too low, you might need to stop Subsys (fentanyl) and be treated with corticosteroids.

              risk-warning

              Seizures

              • Risk factors: History of seizure conditions

                If you've had a seizure in the past, opioids can raise the risk of having seizures more often. Subsys (fentanyl) can also raise your risk of seizures in certain situations. Get medical help immediately if you have a seizure while you're taking this medication.

                More on Subsys (fentanyl) warnings

                basics-icon

                What are the side effects of Subsys (fentanyl)?

                The following side effects may get better over time as your body gets used to the medication. Let your healthcare provider know immediately if you continue to experience these symptoms or if they worsen over time.

                Common Side Effects

                • Vomiting (16%)
                • Nausea (10%)
                • Constipation (10%)
                • Shortness of breath (10%)
                • Weakness (10%)
                • Anxiety (6%)

                Other Side Effects

                • Sleepiness
                • Dizziness
                • Stomach pain
                • Low appetite
                • Depression
                • Confusion
                • Cough
                • Itching

                Serious Side Effects

                Contact your healthcare provider immediately if you experience any of the following.
                • Dangerously slow breathing: trouble breathing; bluish-colored lips, fingers, or toes
                • Accidentally taking too much (overdose): not responding to sound or touch, slowed breathing, extreme sleepiness, slow heartbeat, cold or clammy skin
                • Opioid withdrawal: anxiety, suicidal thoughts, irritability, restlessness, runny nose, yawning, sweating, chills, wide pupils
                • Serious allergic reaction: rash, hives, shortness of breath, fast heartbeat, dizziness, feeling warm suddenly

                Source: DailyMed

                The following side effects have also been reported

                Along with its needed effects, a medicine 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 immediately if any of the following side effects occur:

                More common

                Black, tarry stools

                blurred vision

                chest pain

                confusion

                convulsions

                cough

                decreased urine

                difficult or labored breathing

                dizziness

                dry mouth

                fainting

                fever or chills

                increased thirst

                irregular heartbeat

                lightheadedness

                loss of appetite

                lower back or side pain

                mood changes

                muscle pain or cramps

                nausea or vomiting

                nervousness

                numbness or tingling in the hands, feet, or lips

                painful or difficult urination

                pale skin

                pounding in the ears

                rapid breathing

                sneezing

                sore throat

                sunken eyes

                swelling of the hands, ankles, feet, or lower legs

                tightness in the chest

                troubled breathing with exertion

                ulcers, sores, or white spots in the mouth

                unusual bleeding or bruising

                unusual tiredness or weakness

                wrinkled skin

                Less common

                Abdominal or stomach pain

                change in walking and balance

                clumsiness or unsteadiness

                decreased awareness or responsiveness

                decreased frequency of urination

                headache

                muscle twitching or jerking

                pounding in the ears

                rhythmic movement of the muscles

                seeing, hearing, or feeling things that are not there

                seizures

                severe constipation

                severe sleepiness

                shakiness in the legs, arms, hands, or feet

                slow or fast heartbeat

                thinking abnormalities

                trembling or shaking of the hands or feet

                Get emergency help immediately if any of the following symptoms of overdose occur:

                Symptoms of overdose

                Extremely shallow or slow breathing

                Some side effects 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

                Back pain

                diarrhea

                difficulty having a bowel movement (stool)

                difficulty with moving

                discouragement

                feeling sad or empty

                irritability

                lack or loss of strength

                loss of interest or pleasure

                muscle stiffness

                pain in the joints

                sleepiness or unusual drowsiness

                tiredness

                trouble concentrating

                trouble sleeping

                weight loss

                Less common

                Changes in vision

                excessive muscle tone

                feeling of constant movement of self or surroundings

                feeling of warmth or heat

                flushing or redness of the skin, especially on the face and neck

                irritation, pain, or sores at the site of application

                itching skin

                muscle tension or tightness

                rash

                sensation of spinning

                sweating

                Incidence not known

                Tooth pain

                trouble with gums

                trouble with teeth

                Other side effects not listed may also occur in some patients. If you notice any other effects, check with 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.

                pros-and-cons

                Pros and cons of Subsys (fentanyl)

                thumbs-up

                Pros

                Can work within 5 minutes to relieve breakthrough cancer pain

                Comes with a portable pouch and child-resistant lock and latches for safe storage and handling

                thumbs-down

                Cons

                Only for cancer pain (not for other types of short-term pain)

                Can only be used if you already take opioids around-the-clock (opioid-tolerant)

                Can have a lot of side effects, such as nausea, vomiting, constipation, and sleepiness

                pharmacist-tips

                Pharmacist tips for Subsys (fentanyl)

                pharmacist
                • Opioid medications can make you sleepy and affect your ability to think, react, and focus. Don't drive or do activities that you need to be alert for until you know how this medication affects you.

                  • Don't drink alcohol while you're taking opioids like Subsys (fentanyl). Mixing alcohol and opioids together can make you very sleepy or dizzy or unable to think clearly. This can raise your risk for accidental injuries or overdose.

                    • Opioid medications like Subsys (fentanyl) can cause constipation. Ask your provider for recommendations if you become constipated while you're taking this medication. Some over-the-counter medications for constipation include senna (Sennokot) and polyethylene glycol (Miralax). There are also prescription medications for constipation if you need even more relief.

                      • Tell your providers and pharmacists about all the medications you're taking or planning to take with opioids like Subsys (fentanyl). Many medications can interact with Subsys (fentanyl) and cause the pain medication to work less well or raise your risk for harm, such as slow breathing, severe sleepiness, or even overdose.

                        • Your provider or pharmacist will talk to you about naloxone (Narcan), a medication that can be used in emergency situations for accidental opioid overdose. Tell your family and close friends where you'll keep it in case an overdose happens. Signs of an overdose include slowed breathing, sleepiness, muscle weakness, small pupils, cold or clammy skin, or unresponsiveness. If you use naloxone (Narcan) for an overdose, you should still call 911 because its effects are temporary.

                          More on Subsys (fentanyl) tips

                          faqs

                          Frequently asked questions about Subsys (fentanyl)

                          Is Subsys (fentanyl) still available?
                          No, Subsys (fentanyl) is no longer available. It's not clear why Subsys (fentanyl) was discontinued and removed from the market.
                          Is Subsys (fentanyl) an opioid?
                          Yes, Subsys (fentanyl) is an opioid medication. It's specifically used for managing breakthrough cancer pain in adults.
                          How is Subsys (fentanyl) given?
                          Subsys (fentanyl) is given as a spray under your tongue to relieve an episode of breakthrough cancer pain.
                          How many sprays are in Subsys (fentanyl)?
                          Each Subsys (fentanyl) spray device contains one spray. After you take your dose, you should place the Subsys (fentanyl) spray device in a disposal bag that's provided in the carton, seal the bag, and throw it away in the trash.
                          Why is Subsys (fentanyl) dangerous?
                          In general, fentanyl can be dangerous because it's a very powerful opioid. It has a high risk of causing dangerously slowed breathing and overdose. For this reason, it's important to take opioid medications exactly as prescribed. Contact your provider to discuss your options if you have concerns with how well your medication is working to treat your pain. Don't simply change the dose on your own, especially with any opioid medications.
                          Does Narcan work for Subsys (fentanyl)?
                          Yes, Narcan (naloxone) will work to reverse the effects of Subsys (fentanyl), if needed (such as for accidental overdose or very slowed breathing). Narcan (naloxone) is a medication called an opioid antagonist that helps reverse the effects of opioids like Subsys (fentanyl). If you need to use Narcan (naloxone), be sure to still call 911 for help because the effects of the reversal medication are temporary.
                          What do Subsys (fentanyl) withdrawal symptoms look like?
                          Opioid withdrawal can cause many side effects in different parts of body at different times. Opioid withdrawal symptoms can include pain, blurry vision, sweating, a racing heart, restlessness, and irritability. Fentanyl is considered a short-acting opioid, meaning it works and wears off fast. But withdrawal symptoms are possible if you depend on the medication for pain for a long time and suddenly stop using it or if you lower your dose too fast. Withdrawal symptoms could potentially last for up to 10 days. It's important to take opioids exactly as prescribed and talk to your provider if you're interested in changing your dose.
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                          dosage

                          Subsys (fentanyl) dosage forms

                          Typical dosing for Subsys (fentanyl)

                          Your provider will work with you to prescribe the right dose of Subsys (fentanyl) for your individual needs. It's recommended to use the lowest dose possible for the shortest duration of time to manage your pain.

                          The typical starting dose is one spray (100 mcg) under your tongue (sublingually) to treat one episode of breakthrough pain. Ask your provider what you should do if your breakthrough pain isn't relieved after you use Subsys (fentanyl).

                          Wait at least 4 hours before treating another episode of breakthrough pain.

                          interactions

                          Interactions between Subsys (fentanyl) and other drugs

                          Subsys (fentanyl) may interact with certain medications or supplements. Always let your doctor and pharmacist know about any other medications or supplements (including prescribed and over-the-counter medications, vitamins, and dietary or herbal supplements) that you are currently taking. The list below does not include all possible drug interactions with Subsys (fentanyl). Please note that only the generic name of each medication is listed below.

                          Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.

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

                          contraindications-icon

                          Subsys (fentanyl) contraindications

                          Contraindications are specific health conditions or situations in which a person should not take a medication due to safety concerns. If you have any of the following conditions or if any of the following apply to you, let your healthcare provider know because Subsys (fentanyl) will not be safe for you to take.
                          • Not taking around-the-clock opioids (opioid non-tolerance)

                          • Short-term pain, such as headache, migraine, dental pain, or pain after surgery

                          • Severe asthma

                          • Stomach or intestinal blockage (paralytic ileus)

                          • Allergy to other fentanyl products

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                          References

                          Best studies we found

                          American Cancer Society. (2024). Pain in people with cancer.

                          Centers for Disease Control and Prevention. (2022). About opioid use during pregnancy.

                          Insys Therapeutics, Inc. (2021). Subsys [package insert]. DailyMed.

                          View All References (6)

                          Jansson, L. M., et al. (2019). Neonatal abstinence syndrome. Pediatric Clinics of North America.

                          McNicol, E., et al. (2003). Management of opioid side effects in cancer-related and chronic noncancer pain: A systematic review. The Journal of Pain.

                          National Institute of Diabetes and Digestive and Kidney Diseases. (2018). Adrenal insufficiency & Addison’s disease.

                          National Institute of Diabetes and Digestive and Kidney Diseases. (2018). Symptoms & causes of adrenal insufficiency & Addison's disease.

                          Taylor D. R. (2013). Single-dose fentanyl sublingual spray for breakthrough cancer pain. Clinical Pharmacology: Advances and Applications.

                          U.S. Food and Drug Administration. (2020). Questions and answers: FDA approves a class Risk Evaluation and Mitigation Strategy (REMS) for transmucosal immediate-release fentanyl (TIRF) medicines.

                          GoodRx Health has strict sourcing policies and relies on primary sources such as medical organizations, governmental agencies, academic institutions, and peer-reviewed scientific journals. Learn more about how we ensure our content is accurate, thorough, and unbiased by reading our editorial guidelines.
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