Name: Subsys


  • Insys Therapeutics, Inc.

Subsys Usage

Take fentanyl exactly as prescribed.

This medication comes in nasal spray, sublingual spray, sublingual tablet, lozenge, and transdermal patch forms. The dose and frequency of administration will vary with the indication and dosage form.


Instructions for use of nasal spray:

To use fentanyl nasal spray, begin by blowing your nose, if you have a runny nose. Remove the protective cap from the bottle tip and hold the bottle so that the nozzle is between your first and second fingers and your thumb is on the bottom. Sit upright and insert the tip of the bottle approximately 1/2 inch into one nostril, pointing the tip toward the bridge of your nose. Close your other nostril with your finger. Press down firmly on the finger grips until you hear a ''click'' sound. You may not feel the spray go into your nose, but as long as the number in the counting window increases by one, the spray has been given. Breathe in gently through your nose and out through your mouth one time after spraying. Do not sniff after spraying the medication into your nose. If your doctor wants you to use two sprays, repeat the adminsitration, using your other nostril. Stay sitting down for at least 1 minute after using fentanyl nasal spray. Do not blow your nose for at least 30 minutes after using fentanyl nasal spray.


Instructions for use of sublingual spray:

To use the sublingual spray, first remove the fentanyl sublingual spray unit from the blister package by cutting along the dashed line with a pair of scissors. Swallow any saliva in your mouth. Hold the fentanyl sublingual spray unit upright using your index and middle fingers and thumb. Point the nozzle into your mouth and under your tongue. Squeeze your fingers and thumb together to spray the medication under your tongue. Hold the medication under your tongue for 30 to 60 seconds. Do not spit out the medication or rinse your mouth. The fentanyl sublingual spray is a one-time use unit and will remain locked after use.


Instructions for use of sublingual tablets:

Place ABSTRAL (fentanyl) sublingual tablets on the floor of the mouth directly under the tongue immediately after removal from the blister pack. Do not chew, suck, or swallow ABSTRAL tablets. Allow ABSTRAL tablets to completely dissolve in the sublingual cavity. Do not eat or drink anything until the tablet is completely dissolved. If you have a dry mouth, use water to moisten the buccal mucosa before taking ABSTRAL.


Instructions for use of lozenges:

Place ACTIQ in your mouth between your cheeks and gums and actively suck on the medicine. Move the lozenge around in your mouth, especially along the inside of your cheeks. Twirl the handle often. Finish the ACTIQ unit completely in 15 minutes to get the most relief. If you finish ACTIQ too quickly, you will swallow more of the medicine and get less relief. Do not bite or chew ACTIQ. You will get less relief for your breakthrough cancer pain.


Instructions for use of transdermal patches:

A fentanyl transdermal system may be applied to the chest, back, flank, or upper arm in a place where there is no hair. Patches should not be placed on skin that is oily, burned, cut, irritated, or damaged. Avoid areas that are sensitive or that move around a lot. Do not shave the area where the patch will be placed.

A patch may be applied at any time of the day, but you should change the patch around the same time every 3 days. Do not wear more than one patch at a time, unless directed by your doctor. Before applying the patch, clean the skin and pat the area dry. Open the patch’s protective pouch and peel the plastic backing away from the patch. Take care not to touch the sticky side of the patch. Press the patch to the skin with the palm of your hand for at least 30 seconds. Make sure it sticks well, especially at the edges. Wash your hands after applying the patch. After 3 days, remove the patch and apply a new one in a different spot. If the patch falls off before 3 days, do not replace it with a new patch; wait until 3 days after you put it on to apply a new patch.



This medication is also available in an injectable form to be given directly into a vein (IV) or the muscle (IM) by a healthcare professional.

Subsys Overdose

If you take too much fentanyl, call your healthcare provider or local Poison Control Center, or seek emergency medical attention right away.

If fentanyl is administered by a healthcare provider in a medical setting, it is unlikely that an overdose will occur. However, if overdose is suspected, seek emergency medical attention.

Uses For Subsys

Fentanyl is used to treat severe pain in cancer patients. It is used for breakthrough cancer pain, which are flares of pain that “break through” after a routine pain medicine has been used. Fentanyl belongs to the group of medicines called narcotic analgesics. It is only used in patients who are already taking narcotic analgesics.

Fentanyl acts in the central nervous system (CNS) to relieve pain. Some of its side effects are also caused by actions in the CNS. When a narcotic is used for a long time, it may become habit-forming or cause mental or physical dependence. However, people who have continuous pain should not let the fear of dependence keep them from using narcotics to relieve pain. Mental dependence (addiction) is not likely to occur when narcotics are used for this purpose. Physical dependence may lead to withdrawal side effects if treatment is stopped suddenly. Withdrawal side effects can usually be prevented by gradually reducing the dose over a period of time before the medicine is stopped completely. Talk to your doctor about the benefits of this medicine and how to prevent withdrawal side effects.

This medicine is available only with your doctor's prescription. The Abstral®, Actiq®, Fentora®, Onsolis®, and Subsys® products are only available under a restricted distribution program. You will have to read and sign papers that explain how the medicine is used when you pick up your prescription.

Consumer Information Use and Disclaimer

  • If your symptoms or health problems do not get better or if they become worse, call your doctor.
  • Do not share your drugs with others and do not take anyone else's drugs.
  • Keep a list of all your drugs (prescription, natural products, vitamins, OTC) with you. Give this list to your doctor.
  • Talk with the doctor before starting any new drug, including prescription or OTC, natural products, or vitamins.
  • This medicine comes with an extra patient fact sheet called a Medication Guide. Read it with care. Read it again each time this medicine (Subsys) is refilled. If you have any questions about this medicine, please talk with the doctor, pharmacist, or other health care provider.
  • If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

Review Date: October 4, 2017


Subsys is contraindicated in:

  • Opioid non-tolerant patients: Life-threatening respiratory depression and death could occur at any dose in opioid non-tolerant patients [see Indications and Usage (1); Warnings and Precautions (5.1)].
  • Acute or postoperative pain including headache/migraine and dental pain, or in the emergency department [see Indications and Usage (1)].
  • Acute or severe bronchial asthma in an unmonitored setting or in the absence of resuscitative equipment [see Warnings and Precautions (5.9)].
  • Known or suspected gastrointestinal obstruction, including paralytic ileus [see Warnings and Precautions (5.14)].
  • Known hypersensitivity (e.g., anaphylaxis) to fentanyl or components of Subsys [see Adverse Reactions (6.2)].

Drug Interactions

Table 6 includes clinically significant drug interactions with Subsys.

Table 6. Clinically Significant Drug Interactions with Subsys
Inhibitors of CYP3A4
Clinical Impact:

The concomitant use of Subsys and CYP3A4 inhibitors can increase the plasma concentration of fentanyl, resulting in increased or prolonged opioid effects, particularly when an inhibitor is added after a stable dose of Subsys is achieved [see Warnings and Precautions (5.3)].

After stopping a CYP3A4 inhibitor, as the effects of the inhibitor decline, the fentanyl plasma concentration will decrease [see Clinical Pharmacology (12.3)], resulting in decreased opioid efficacy or a withdrawal syndrome in patients who had developed physical dependence to fentanyl.


If concomitant use is necessary, consider dosage reduction of Subsys until stable drug effects are achieved. Monitor patients for respiratory depression and sedation at frequent intervals.

If a CYP3A4 inhibitor is discontinued, consider increasing the Subsys dosage until stable drug effects are achieved. Monitor for signs of opioid withdrawal.

Examples Macrolide antibiotics (e.g., erythromycin), azole-antifungal agents (e.g. ketoconazole), protease inhibitors (e.g., ritonavir)
CYP3A4 Inducers
Clinical Impact:

The concomitant use of Subsys and CYP3A4 inducers can decrease the plasma concentration of fentanyl [see Clinical Pharmacology (12.3)], resulting in decreased efficacy or onset of a withdrawal syndrome in patients who have developed physical dependence to fentanyl [see Warnings and Precautions (5.3)].

After stopping a CYP3A4 inducer, as the effects of the inducer decline, the fentanyl plasma concentration will increase [see Clinical Pharmacology (12.3)], which could increase or prolong both the therapeutic effects and adverse reactions, and may cause serious respiratory depression.

Intervention: If concomitant use is necessary, consider increasing the Subsys dosage until stable drug effects are achieved. Monitor for signs of opioid withdrawal. If a CYP3A4 inducer is discontinued, consider Subsys dosage reduction and monitor for signs of respiratory depression.
Examples Rifampin, carbamazepine, phenytoin
Benzodiazepines and other Central Nervous System (CNS) Depressants
Clinical Impact: Due to additive pharmacologic effect, the concomitant use of benzodiazepines or other CNS depressants including alcohol, increases the risk of respiratory depression, profound sedation, coma, and death.
Intervention: Reserve concomitant prescribing of these drugs for use in patients for whom alternative treatment options are inadequate. Limit dosages and durations to the minimum required. Follow patients closely for signs of respiratory depression and sedation [see Warnings and Precautions (5.1)].
Examples: Benzodiazepines and other sedatives/hypnotics, anxiolytics, tranquilizers, muscle relaxants, general anesthetics, antipsychotics, other opioids, alcohol.
Serotonergic Drugs
Clinical Impact: The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome [see Warnings and Precautions (5.10)].
Intervention: If concomitant use is warranted, carefully observe the patient, particularly during treatment initiation and dose adjustment. Discontinue Subsys if serotonin syndrome is suspected.
Examples: 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 (e.g., mirtazapine, trazodone, tramadol), monoamine oxidase (MAO) inhibitors (those intended to treat psychiatric disorders and also others, such as linezolid and intravenous methylene blue).
Monoamine Oxidase Inhibitors (MAOIs)
Clinical Impact: MAOI interactions with opioids may manifest as serotonin syndrome [see Warnings and Precautions (5.10)] or opioid toxicity (e.g., respiratory depression, coma) [see Warnings and Precautions (5.2)].
Intervention: The use of Subsys is not recommended for patients taking MAOIs or within 14 days of stopping such treatment.
Examples: phenelzine, tranylcypromine, linezolid
Mixed Agonist/Antagonist and Partial Agonist Opioid Analgesics
Clinical Impact: May reduce the analgesic effect of Subsys and/or precipitate withdrawal symptoms.
Intervention: Avoid concomitant use.
Examples: butorphanol, nalbuphine, pentazocine, buprenorphine,
Muscle Relaxants
Clinical Impact: Fentanyl may enhance the neuromuscular blocking action of skeletal muscle relaxants and produce an increased degree of respiratory depression.
Intervention: Monitor patients for signs of respiratory depression that may be greater than otherwise expected and decrease the dosage of Subsys and/or the muscle relaxant as necessary.
Clinical Impact: Opioids can reduce the efficacy of diuretics by inducing the release of antidiuretic hormone.
Intervention: Monitor patients for signs of diminished diuresis and/or effects on blood pressure and increase the dosage of the diuretic as needed.
Anticholinergic Drugs
Clinical Impact: The concomitant use of anticholinergic drugs may increase risk of urinary retention and/or severe constipation, which may lead to paralytic ileus.
Intervention: Monitor patients for signs of urinary retention or reduced gastric motility when Subsys is used concomitantly with anticholinergic drugs.

Subsys Description

Subsys (fentanyl sublingual spray) is an opioid agonist, available as a sublingual spray designed to deliver doses of 100, 200, 400, 600, 800, 1200 and 1600 mcg of fentanyl. The chemical name of fentanyl is N-phenyl-N-[1-(2-phenylethyl)-4-piperidinyl]propanamide.

Fentanyl is a highly lipophilic compound (octanol-water partition coefficient at pH 7.4 is 860:1) that is freely soluble in ethanol and methanol and practically insoluble in water (1:40). The molecular weight of the free base is 336.47. The pKa is 8.4.

The inactive ingredients in Subsys include: dehydrated alcohol 63.6% (V/V), purified water, propylene glycol, xylitol, and L-menthol.