Comorbidity of mental disorders and substance use: a brief guide for the primary care clinician
11.3 Major clinical issues with gambling and cannabis/ hallucinogen use
- There is a significant association between cannabis use and problem gambling, with more severe problem gambling being associated with greater intensity of cannabis use and vice versa.
- CBT approaches that target both gambling and cannabis use may be effective in people with comorbid cannabis use disorders and problem gambling.
11.3.1 Effects of cannabis and other hallucinogens on problem gambling
- As is the case with the general population, cannabis is the most commonly used illicit substance amongst people with problem gambling(432, 464, 488).
- There is a significant association between cannabis use and problem gambling with more severe problem gambling being associated with greater intensity of cannabis use and vice versa(365, 436, 440, 443, 464, 468, 470).
- Additional hallucinogen use is also reported by people with problem gambling although not to the same extent as cannabis(432, 464).
11.3.2 Interactions between cannabis and other hallucinogens and therapeutic agents for problem gambling
- Cannabis can exacerbate the sedative effects of tricyclic antidepressants and mood stabilisers (lithium and sodium valproate). This increases the risk of impaired driving and injury as well as overdosex.
- LSD may induce a serotonin syndrome (Appendix 1), therefore caution should be exercised when prescribing SSRIs or MAO-Ix(127).
- Cannabis and antidepressants are metabolised by CYP 450 enzymes which may result in the inhibition or induction of either drug group. Therefore, individuals should be monitored closely to ensure responses are within the therapeutic rangex.
11.3.3 Management approaches to comorbid problem gambling and cannabis use
- Abstinence from cannabis is a difficult goal to achieve in cannabis dependent people(128).
- In the absence of other proven forms of treatment, CBT is, at present, the most widely employed form of treatment for cannabis use****(128).
- CBT, in particular, exposure therapy is effective at reducing problem gambling****(441-443).
- CBT approaches that target both gambling and cannabis use may be effective in people with comorbid cannabis use disorders and problem gambling. However, studies are yet to confirm this.