From the Guidelines
For patients on methadone experiencing pruritus, naltrexone is the first-choice recommendation as it is effective in treating opioid-induced generalized pruritus without visible skin signs. This approach is based on the British Association of Dermatologists' guidelines for the investigation and management of generalized pruritus in adults without an underlying dermatosis, 2018 1. The guidelines suggest that if cessation of opioid therapy is impossible, naltrexone should be considered as the primary treatment option.
Some key points to consider in the management of pruritus in patients on methadone include:
- Naltrexone's effectiveness in treating opioid-induced pruritus without compromising analgesia
- Methylnaltrexone as an alternative option for patients who cannot tolerate naltrexone
- Other antipruritic agents like ondansetron, droperidol, mirtazapine, or gabapentin may be considered as alternatives, although the strength of recommendation for these is lower (Strength of recommendation D) 1
- Ensuring adequate hydration and maintaining skin barrier function through regular moisturizer use is also crucial in managing pruritus
In clinical practice, it's essential to weigh the benefits and risks of each treatment option, considering the patient's specific situation and medical history. Given the potential for opioid-induced pruritus to significantly impact quality of life, naltrexone's effectiveness makes it a preferred choice for managing pruritus in patients on methadone, as supported by the guidelines 1.
From the FDA Drug Label
Skin and Appendages: pruritis, urticaria, other skin rashes, and rarely, hemorrhagic urticaria The treatment for pruritis in a patient on methadone is not specified in the drug label.
- Pruritis is listed as a possible adverse reaction, but no guidance is provided on how to manage it.
- No specific treatment options are mentioned for pruritis in the context of methadone use 2.
From the Research
Treatment for Pruritis with Patients on Methadone
- Pruritus is a common adverse effect of opioid medications, including methadone, and can have a significant impact on patients' comfort and quality of life 3.
- The mechanisms of opioid-induced pruritus are complex and involve both peripheral and central pathways, making treatment challenging 3.
- Several studies have investigated the use of opioid receptor antagonists, such as naloxone and naltrexone, for the management of opioid-induced pruritus, with some showing promising results 4, 5.
- A systematic review of randomized trials found that naloxone, naltrexone, nalbuphine, and droperidol are efficacious in preventing opioid-induced pruritus, but the minimal effective doses remain unknown 5.
- In patients taking methadone for opioid use disorder, managing acute pain can be complicated, and evidence suggests that continuing methadone may reduce the need for additional opioids 6.
- A pilot study found that increasing the maintenance methadone dose by 30% or adding gabapentin did not improve analgesia in patients on methadone, but interindividual variability was evident 7.
- Further research is needed to optimize pain management strategies in patients on methadone, including the treatment of pruritis, to improve patient outcomes and quality of life 3, 6, 7.
Possible Treatment Options
- Opioid receptor antagonists, such as naloxone and naltrexone, may be effective in relieving opioid-induced pruritus 4, 5.
- Mixed agonist and antagonist medications, such as nalbuphine, may also be useful in managing opioid-induced pruritus 5.
- A multimodal analgesic treatment regimen, including a mixed antagonist and κ agonists, may be the best approach for managing opioid-induced pruritus and pain 3.
- Continuing methadone or buprenorphine in patients with opioid use disorder may reduce the need for additional opioids and improve pain management 6.