From the Research
The conversion factor from Belbuca (buccal buprenorphine) to Butrans (transdermal buprenorphine) is approximately 75:1, as supported by the most recent and highest quality study available 1. This means that 75 mcg/hour of Butrans is roughly equivalent to 300 mcg of Belbuca twice daily. For example, a patient taking Belbuca 300 mcg twice daily (600 mcg total daily dose) would convert to approximately Butrans 7.5 mcg/hour patch. When making this conversion, it's essential to consider that these formulations have different bioavailability due to their distinct routes of administration. Belbuca is administered as a buccal film with higher bioavailability, while Butrans is a transdermal patch that delivers medication continuously over 7 days. Clinicians should monitor patients closely after conversion for adequate pain control and side effects, and may need to adjust dosing based on individual response. Due to the risk of respiratory depression with opioids, it's advisable to start with a conservative conversion and titrate as needed, especially in opioid-naive patients or those with respiratory conditions. Some key points to consider when converting between these two formulations include:
- The pharmacokinetics of transdermal buprenorphine, as described in a study published in the Journal of Pain and Symptom Management 2, which demonstrated sustained and consistent steady-state plasma levels with once-weekly application.
- The efficacy and tolerability of low-dose transdermal buprenorphine compared to sublingual buprenorphine, as reported in a randomized, double-blind, double-dummy study published in the Journal of Pain and Symptom Management 3.
- The importance of considering the ceiling effect of buprenorphine on respiratory depression, as well as its analgesic efficacy and adverse effect profile, when selecting a formulation for chronic pain management, as discussed in a review published in Drugs 4. However, the most recent study 1 provides the most relevant guidance for conversion between Belbuca and Butrans, emphasizing the need for careful consideration of individual patient factors and close monitoring during the conversion process.