Background
To date, no drugs have been approved for gambling disorder. Numerous publications have described
the value of opioid antagonists. Indeed, the mesocorticolimbic dopaminergic pathway has been
suggested as the underlying cause of reward-seeking behaviour, and it is modulated by the opioid
system.
Objective
This study aims to evaluate the relevance of opioid antagonists for treating GD.
Method
A systematic literature review was conducted. A search of the PubMed electronic database, PsycINFO
and the Cochrane Systematic Review Database without any limits was performed.
Results
There is little information concerning the effects of opioid antagonists on GD. The total search with
“nalmefene and gambling” without any limits revealed only 11 articles. The search with “naltrexone
and gambling” without any limits generated 47 articles. Nevertheless, the best available data support
the use of opioid antagonists, particularly in individuals with a history of alcohol use disorder or
strong gambling urges.
Conclusion
Future trials are still needed. Indeed, opioid antagonists effectiveness has been investigated in only a
limited number of patients, clinical trials do not reflect the heterogeneity of GD and there is little
knowledge of the predictive factors of response to treatments. Moreover, differential affinity to
nalmefene for kappa receptors may be associated with a particular effect in a yet to be defined
addiction phenotype. Head to head comparisons between naltrexone and nalmefene would be helpful
in combining with other medication or psychotherapy. The identification of the subgroups of patients
that are more likely to benefit from opioid antagonists should be a goal