1.1.4. Sublingual Spray (Subsys®)

With the exception of patients previously treated with fentanyl transmucosal lozenges, treatment with fentanyl sublingual spray should be initiated with a 100 mcg dose. If patients do not achieve adequate analgesia within 30 minutes, a second fentanyl sublingual spray dose of the same strength may be administered. No more than two doses should be administered for any breakthrough pain episode. Patients must wait at least 4 hours before administering fentanyl sublingual spray for another episode of breakthrough pain. Patients should be prescribed only a titration supply of 100 mcg dose units during titration to minimize the number of available units during titration. If pain relief for the breakthrough episode is not relieved with the 100 mcg dose, titrate doses upward to 200 mcg, 400 mcg, 600 mcg, 800 mcg, 1200 mcg, or 1600 mcg per dose. Patients previously treated with fentanyl transmucosal lozenges should receive a modified initial sublingual spray dose, based on the transmucosal lozenge dose that had previously been utilized. Dosage conversions between fentanyl transmucosal lozenges and sublingual spray are summarized in Table 3.

Once an effective fentanyl sublingual spray dose has been determined, patients should be maintained on this dose. If pain is not effectively managed with this dose of fentanyl sublingual spray, a patient may use a second dose as directed by their health care provider, with no more than two doses being used to treat any breakthrough pain episode. Again, patients must wait at least four hours before treating subsequent breakthrough pain episodes. Increase the fentanyl sublingual spray dose only when treatment at the current dose fails to provide pain relief for several episodes. To reduce the risk of overdose, patients should have only one fentanyl sublingual spray dosage strength available at any time. If more than four breakthrough pain episodes happen per day, the long-term opiate maintenance dose should be re-evaluated. In patients with Grade 1 mucositis, fentanyl sublingual spray may result in higher drug serum concentrations. For patients with Grade 2 mucositis, avoid sublingual fentanyl use unless the benefits outweigh the risks of increased drug exposure^{4, 7-11}.