Is naltrexone appropriate for treating a 17-year-old adolescent with cannabis use disorder?

Naltrexone is NOT Appropriate for Treating Cannabis Use Disorder in a 17-Year-Old

Naltrexone is not FDA-approved for cannabis use disorder at any age, and current evidence-based guidelines recommend motivational interviewing and behavioral therapies as first-line treatment for adolescent cannabis use disorder, not pharmacotherapy. 1, 2

FDA Approval Status and Lack of Evidence

• Naltrexone is FDA-approved only for alcohol dependence and opioid blockade—not for cannabis use disorder. 3
• The FDA label explicitly states naltrexone "has not been shown to affect the use of cocaine or other non-opioid drugs of abuse," which includes cannabis. 3
• Buprenorphine is the only FDA-approved medication for substance use disorder in adolescents (approved down to age 16 for opioid use disorder only). 1, 4

Guideline-Recommended Treatment Approach

The American Academy of Child and Adolescent Psychiatry recommends psychosocial interventions as the standard of care for adolescent cannabis use disorder: 1

• Motivational interviewing paired with decisional balance exercises and goal setting forms the core treatment approach. 1, 2
• Family-based ecological treatment and cognitive-behavioral therapy remain well-established approaches for adolescent substance use. 1
• Contingency management is effective for promoting abstinence and increasing treatment attendance in youth with substance use disorders. 1

Limited and Conflicting Research Evidence

While some adult studies show promise, the evidence for naltrexone in cannabis use disorder is insufficient and not applicable to adolescents:

• One adult laboratory study showed naltrexone reduced cannabis self-administration in daily users, but this was in non-treatment-seeking adults, not adolescents. 5
• A small open-label pilot study (n=12 adults) showed feasibility but no significant reduction in THC concentrations or daily cannabis use. 6
• One small study (n=59 adults) suggested naltrexone efficacy, but this was not a placebo-controlled trial and has not been replicated. 7
• A 2026 systematic review concluded there are no FDA-approved medications for cannabis use disorder, emphasizing the reliance on psychosocial interventions. 8

Critical Developmental Considerations

• Off-label pharmacotherapy for adolescent substance use disorders requires substantially more research before implementation. 1, 4
• Developmental changes in drug disposition and pharmacodynamic pathways must be considered when using naltrexone in pediatric populations, and evidence is primarily derived from adult studies. 9
• Only three medications have been tested for adolescent cannabis use disorder, and naltrexone is not among them (N-acetylcysteine showed the most promise). 4

Common Pitfalls to Avoid

• Do not prescribe naltrexone off-label for adolescent cannabis use disorder when evidence-based psychosocial interventions have not been attempted first. 1, 2
• Naltrexone has intrinsic side effects including decreased appetite, stomach upset, and headache that may be particularly problematic in adolescents. 5
• The medication requires high compliance to be effective, which is challenging in adolescent populations without external enforcement mechanisms. 3

Recommended Clinical Approach

For this 17-year-old with cannabis use disorder, implement the following evidence-based algorithm: 1, 2

1. Initiate motivational interviewing as the backbone of treatment
2. Engage family-based services and ecological family therapy
3. Add cognitive-behavioral therapy or contingency management based on severity
4. Provide harm-reduction resources including naloxone kits if polysubstance use is present 2
5. Reserve pharmacotherapy only for cases where psychosocial interventions have failed and consider agents with better evidence (such as N-acetylcysteine in research settings) 4