Do not use Subsys to replace any other form of fentanyl, such as Actiq, Fentora, Onsolis, Duragesic, Lazanda, or generic brands of fentanyl (injection, skin patch, dissolving film, or "lollipop" device). If you switch to Subsys from another form of fentanyl, you will not use the same dose. You must start with the lowest dose (100 micrograms). Your doctor may change your dose to make sure you get the best results. Point the Subsys spray nozzle into your mouth, lift your tongue, and spray the medicine under your tongue. Hold the liquid under the tongue for 30 to 60 seconds. Do not spit, swallow, or rinse your mouth during this time. You may use a second dose of Subsys 30 minutes after the first. Use only the same strength and amount you used for the first dose. Call your doctor if you still have pain after taking the second tablet. Do not take more than 2 doses for each episode of breakthrough cancer pain.
Subsys is indicated for the management of breakthrough pain in adult cancer patients who are already receiving and who are tolerant to around-the-clock opioid therapy for their underlying persistent cancer pain. Patients considered opioid tolerant are those who are taking around-the-clock medicine consisting of at least 60 mg of oral morphine daily, at least 25 mcg of transdermal fentanyl/hour, at least 30 mg of oral oxycodone daily, at least 8 mg of oral hydromorphone daily or an equianalgesic dose of another opioid daily for a week or longer. Patients must remain on around-the-clock opioids when taking Subsys.
Common Subsys side effects may include: constipation, nausea, drowsiness, or headache.