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Drug Name:


Generic Name and Formulations:
Fentanyl 100mcg, 200mcg, 400mcg, 600mcg, 800mcg; sublingual spray.

Insys Therapeutics, Inc.

Therapeutic Use:

Indications for SUBSYS:

Management of breakthrough pain in opioid-tolerant cancer patients who are already receiving and are tolerant to around-the-clock opioid therapy for their underlying persistent cancer pain. Opioid-tolerant patients are those taking oral morphine ≥60mg/day, transdermal fentanyl ≥25mcg/hr, oral oxycodone ≥30mg/day, oral hydromorphone ≥8mg/day, oral oxymorphone ≥25mg/day, oral hydrocodone ≥60mg/day, or equianalgesic dose of another opioid for ≥1 week.

Limitations Of use:

May be dispensed only to outpatients enrolled in the TIRF REMS ACCESS program; not required for inpatient use.


Do not substitute with other fentanyl products; not equivalent to other fentanyl products on a mcg to mcg basis. Use lowest effective dose for shortest duration. Spray contents into the mouth under the tongue. Individualize. ≥18yrs: Initially 100mcg; monitor and titrate to a tolerable dosage level until adequate analgesia achieved using a single Subsys dose per episode. For each episode, if pain not relieved after 30 mins, may take 1 additional dose at same strength for that episode; max 2 doses per episode. Wait at least 4hrs before treating another episode. If adequate analgesia obtained within 30 mins, treat subsequent episodes with this dose. Titration steps: 100mcg using 1 x 100mcg unit; 200mcg using 1 x 200mcg unit; 400mcg using 1 x 400mcg unit; 600mcg using 1 x 600mcg unit; 800mcg using 1 x 800mcg; 1200mcg using 2 x 600mcg unit; 1600mcg using 2 x 800mcg unit. Maintenance: once an appropriate dose has been established, use that dose for subsequent breakthrough episodes. Limit to ≤4 doses per day. Reevaluate if >4 episodes per day occur. Conversion from Actiq: see full labeling. Cancer patients with oral mucositis: Grade 1: monitor for respiratory and CNS depression (esp. during initiation); Grade ≥2: avoid. Concomitant use or discontinuation of CYP3A4 inhibitors or inducers: monitor closely and consider dose adjustments (see full labeling).


<18yrs: not established.


Opioid non-tolerant patients. Acute or post-op pain (including headache/migraine, dental pain, or ER). Acute or severe bronchial asthma in an unmonitored setting or in the absence of resuscitative equipment. Known or suspected GI obstruction, including paralytic ileus.


Life-threatening respiratory depression; monitor within first 24–72hrs of initiating therapy and following dose increases. Accidental exposure may cause fatal overdose (esp. in children). COPD, cor pulmonale, decreased respiratory reserve, hypoxia, hypercapnia, or pre-existing respiratory depression; monitor and consider non-opioid analgesics. Abuse potential (monitor). Adrenal insufficiency. Head injury. Increased intracranial pressure, brain tumors; monitor. Seizure disorders. CNS depression. Impaired consciousness, coma, shock; avoid. Biliary tract disease. Acute pancreatitis. Bradyarrhythmias. Drug abusers. Renal or hepatic impairment. Reevaluate periodically. Avoid abrupt cessation. Elderly. Cachectic. Debilitated. Pregnancy; potential neonatal opioid withdrawal syndrome during prolonged use. Labor & delivery, nursing mothers: not recommended.


Increased risk of hypotension, respiratory depression, sedation with benzodiazepines or other CNS depressants (eg, non-benzodiazepine sedatives/hypnotics, anxiolytics, general anesthetics, phenothiazines, tranquilizers, muscle relaxants, antipsychotics, alcohol, other opioids); reserve concomitant use in those for whom alternative options are inadequate; limit dosages/durations to minimum required; monitor. During or within 14 days of MAOIs: not recommended. Risk of serotonin syndrome with serotonergic drugs (eg, SSRIs, SNRIs, TCAs, triptans, 5-HT3 antagonists, mirtazapine, trazodone, tramadol, MAOIs, linezolid, IV methylene blue); monitor and discontinue if suspected. Avoid concomitant mixed agonist/antagonist opioids (eg, butorphanol, nalbuphine, pentazocine) or partial agonist (eg, buprenorphine); may reduce effects and precipitate withdrawal symptoms. Potentiated by CYP3A4 inhibitors (eg, macrolides, azole antifungals, protease inhibitors). Antagonized by CYP3A4 inducers (eg, rifampin, carbamazepine, phenytoin). May antagonize diuretics; monitor. Paralytic ileus may occur with anticholinergics.

Pharmacological Class:

Opioid agonist.

Adverse Reactions:

Vomiting, nausea, constipation, dyspnea, somnolence; respiratory depression, severe hypotension, syncope.


Caution patients and caregivers in proper handling and disposal; may be fatal to children.



Generic Availability:


How Supplied:

Blister pack (spray units)—10, 30

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