What is the role of cannabis in the treatment of opioid use disorder and methamphetamine dependence?

Cannabis in the Treatment of Opioid Use Disorder and Methamphetamine Dependence

Cannabis is not recommended as a primary treatment for opioid use disorder or methamphetamine dependence, as there is insufficient evidence supporting its efficacy while established medication-assisted treatments (MAT) with buprenorphine or methadone remain the gold standard for opioid use disorder.

Evidence-Based Treatments for Opioid Use Disorder

First-Line Treatments

• Medication-Assisted Treatment (MAT) is the recommended approach for opioid use disorder, combining medications with behavioral therapies 1, 2
  • Buprenorphine (partial opioid agonist) - office-based treatment with lower overdose risk and flexible dosing 2
  • Methadone (full opioid agonist) - dispensed through specialized opioid treatment programs, recommended for severe dependence 2
  • Naltrexone (opioid antagonist) - requires complete detoxification before initiation, better suited for highly motivated patients 2

Effectiveness of MAT

• MAT with buprenorphine or methadone at least doubles rates of opioid abstinence compared to psychosocial treatment alone 3
• These medications significantly reduce opioid use and retain patients in treatment 3
• Methadone remains the gold standard of care, though buprenorphine/naloxone shows significant efficacy and favorable safety 3

Behavioral Interventions

• Should be used in combination with medications to enhance outcomes 2:
  • Cognitive-behavioral therapy
  • Motivational enhancement therapy
  • Contingency management
  • Group therapy and support groups

Treatment for Methamphetamine Dependence

Current Treatment Options

• No FDA-approved medication-assisted therapy has been determined effective for methamphetamine use disorder 1
• Treatment relies primarily on behavioral interventions:
  • Cognitive-behavioral therapy
  • Contingency management
  • Relapse prevention
  • Motivational enhancement therapy 1

Treatment Challenges

• Patients with opioid and methamphetamine co-use have lower odds of completing short-term residential treatment compared to other substance co-use groups 4
• This population shows higher rates of:
  • Injection drug use (76.0%)
  • Unemployment (62.5%)
  • Treatment non-completion (57.4%)
  • Lower utilization of medications for OUD (84.9% not receiving) 4

Cannabis as a Potential Treatment

Limited Evidence for Cannabis in Opioid Use Disorder

• Some evidence suggests cannabis may be useful as an adjunct to opioid therapy for chronic pain, potentially:
  • Leading to greater cumulative pain relief
  • Reducing opiate use and associated side effects
  • Preventing development of tolerance to opiates 5

Important Caveats

• The evidence for cannabis as a treatment for opioid use disorder or methamphetamine dependence is preliminary and limited
• No major clinical guidelines recommend cannabis as a primary treatment for these conditions 1, 2
• Community-based medical cannabis dispensaries may provide safe access, but lack regulatory oversight 5

Clinical Implications

Treatment Algorithm

1. For opioid use disorder:

   • First-line: Initiate MAT with buprenorphine or methadone combined with behavioral therapy 1, 2
   • Second-line: Consider naltrexone for highly motivated patients who can complete detoxification 2
   • Cannabis is not recommended as a primary treatment

2. For methamphetamine dependence:

   • Implement behavioral therapies (CBT, contingency management) 1
   • No FDA-approved medications are available 1
   • Cannabis is not recommended as a treatment

3. For co-occurring opioid and methamphetamine use:

   • Recognize higher risk of treatment non-completion 4
   • Intensify behavioral supports and consider specialized programs
   • Ensure MAT is provided for the opioid component of addiction 4

Monitoring and Assessment

• Use appropriate biological markers to verify abstinence:
  • Urine drug screens for opioids and methamphetamine
  • Timeline follow-back interviews for self-reported use 1
• Monitor for at least 3 months to assess treatment efficacy 1

Conclusion

While there is some preliminary evidence suggesting cannabis might have a role as an adjunct therapy for pain management in patients using opioids, current guidelines and evidence strongly support medication-assisted treatment with buprenorphine or methadone as the standard of care for opioid use disorder. For methamphetamine dependence, behavioral therapies remain the mainstay of treatment with no FDA-approved medications available. Cannabis should not be considered a primary treatment for either condition based on current evidence.