Recommended Schedule for Switching from 160 mg Methadone to Suboxone Using Microdosing
For patients on high-dose methadone (160 mg), a microdosing strategy is recommended to transition to buprenorphine/naloxone (Suboxone) as it avoids precipitated withdrawal and allows for a more comfortable transition. 1
Microdosing Schedule
- Day 1: Continue full methadone dose (160 mg) and add buprenorphine 0.5 mg once 1
- Day 2: Continue full methadone dose and add buprenorphine 0.5 mg twice daily 1
- Day 3: Continue full methadone dose and add buprenorphine 1 mg twice daily 1
- Day 4: Reduce methadone by 25% (to 120 mg) and increase buprenorphine to 2 mg twice daily 1
- Day 5: Reduce methadone by another 25% (to 80 mg) and increase buprenorphine to 4 mg twice daily 1
- Day 6: Reduce methadone by another 25% (to 40 mg) and increase buprenorphine to 8 mg twice daily 1
- Day 7: Discontinue methadone completely and increase buprenorphine to 12 mg twice daily (24 mg total daily dose) 2, 1
Monitoring and Adjustments
- Monitor for withdrawal symptoms using the Clinical Opiate Withdrawal Score (COWS) throughout the transition 3
- If withdrawal symptoms emerge (COWS >12), consider slowing the methadone taper or increasing the buprenorphine dose 3
- Divided dosing (every 6-8 hours) may be more effective for pain management if that's a concern 2
- The maximum recommended daily dose of buprenorphine is 24 mg for opioid use disorder treatment 2
Alternative Rapid Transition Methods (Hospital Setting Only)
For inpatient settings where rapid transition is necessary:
- Naltrexone-precipitated withdrawal followed by buprenorphine "rescue" can achieve transition within hours 4, 3
- This involves administering naltrexone (25 mg) to precipitate withdrawal, then administering buprenorphine/naloxone (16 mg/4 mg) approximately one hour later 3
- This approach should only be used in controlled inpatient settings with close monitoring 4, 3
Important Considerations
- Microdosing is preferred for high-dose methadone (>100 mg) as traditional methods require lengthy tapers 5
- Traditional methods would require tapering methadone to 30-40 mg before initiating buprenorphine, which could take months at a safe rate of 3% reduction per week 6
- Buprenorphine's high binding affinity for μ-opioid receptors may block effects of other opioids, making this transition challenging 2
- Monitor for side effects including headache and constipation, which may be more pronounced at higher doses 2
Follow-up Care
- Once stabilized on buprenorphine/naloxone, maintain on a single daily dose of 16-24 mg for opioid use disorder treatment 2
- For patients with inadequate response, consider divided dosing or adjusting the maintenance dose within the 4-24 mg range 2
- Close follow-up is essential during the first month after transition to ensure stability and adjust dosing as needed 3