The pharmacological management of gambling disorder: if, when, and how

Comparing efficacy of serotonergic, opioidergic, and glutamatergic drugs in gambling disorder: A pooled analysis of response trajectories versus placebo

Various pharmacological treatments have been explored to alleviate the symptoms and clinical manifestations of gambling disorder (GD) by targeting different neurotransmitter systems. This study retrospectively analyzed subjects with GD treated with serotonergic drugs, opioid antagonist drugs, and glutamatergic drugs compared to placebo, through a pooled analysis of clinical trials conducted at the University of Chicago. The Gambling Symptom Assessment Scale (G-SAS) was employed as the outcome measure. Temporal uniformity was ensured by managing timepoints as follows: baseline, early (4-5 weeks), intermediate (6-8 weeks), and final (10-16 weeks) from the start of treatment. A total of 253 treatment-seeking subjects were included, receiving either glutamatergic drugs (N-acetylcysteine, memantine), opioidergic drugs (naltrexone), serotonergic drugs (paroxetine, escitalopram), or placebo. Within-group analysis demonstrated significant improvement in GD symptoms across all treatment groups. When comparing interventions over time, glutamatergic drugs proved more effective than placebo from the early observation timepoint and onwards. Opioidergic drugs were more effective than placebo at the final observation timepoint, while serotonergic drugs showed no significant effect compared to placebo. Our findings reveal distinct efficacy patterns among the pharmacological classes, likely due to their different mechanisms of action and the various aspects of GD phenomenology they address. The significant placebo effect observed aligns with previous studies, underscoring the complexity of treating GD. In conclusion, given the heterogeneous nature of GD, these results emphasize the necessity of identifying and precisely characterizing GD subtypes to facilitate more tailored treatment approaches.

Linking Striatal Dopaminergic Asymmetry with Personality Traits: Insights from Gambling Disorder

The role of dopamine in the pathophysiology of gambling disorder (GD) remains incompletely understood, with disparate research findings concerning presynaptic and postsynaptic structures and dopaminergic synthesis. The aim of this study was to investigate potential correlations between striatal dopamine transporter (DAT) lateralization and asymmetry index, as assessed by 123I-FP-CIT SPECT, and temperamental traits, as measured by Cloninger's Temperament and Character Inventory (TCI), in GD subjects. Significant associations were found between DAT binding asymmetries in the caudate and putamen and the temperamental dimensions of harm avoidance and novelty seeking. Specifically, high novelty seeking scores correlated with increased DAT binding in the left caudate relative to the right, whereas higher harm avoidance scores corresponded to increased DAT binding in the right putamen relative to the left. These observations potentially imply that the asymmetry in DAT expression in the basal ganglia could be an outcome of hemispheric asymmetry in emotional processing and behavioural guidance. In summary, our study provides evidence supporting the relationship between DAT asymmetries, temperamental dimensions and GD. Future investigations could be directed towards examining postsynaptic receptors to gain a more comprehensive understanding of dopamine's influence within the basal ganglia circuit in disordered gambling. If confirmed in larger cohorts, these findings could have substantial implications for the tailoring of individualized neuromodulation therapies in the treatment of behavioural addictions.

Pharmacological management of gambling disorder: an update of the literature

INTRODUCTION

Gambling disorder (GD) is a mental health condition characterized by persistent and problematic betting behavior. GD generates distress and impairment, and treatment options include psychological and pharmacological interventions.

AREAS COVERED

This narrative review explores existing pharmacological treatments for GD. The following classes of medications were considered: opioid-receptor antagonists (e.g. naltrexone and nalmefene), serotonin reuptake inhibitors (e.g. fluvoxamine, paroxetine, sertraline, escitalopram, and citalopram), glutamatergic agents (e.g. N-acetylcysteine (NAC), acamprosate, and memantine), mood stabilizers (e.g. topiramate, carbamazepine, lithium), and other medications (e.g. modafinil, nefazodone, olanzapine, haloperidol, tolcapone, and bupropion).

EXPERT OPINION

Due to the limitations of the studies reviewed, solid conclusions regarding the optimal choice of pharmacotherapy for individuals with GD are challenging to draw at this time. Despite some medications, such as naltrexone and nalmefene, showing promising results, efficacy has varied across studies. The review highlights current gaps/limitations, including small sample sizes, limited diversity in participant demographics, the need for exploring different gambling subtypes and treatment responses, high placebo response rates, lack of longer-term longitudinal information, limited investigation of neurobiological correlates and co-occurring disorders, and the importance of implementation research. Further research is needed to address these gaps and explore additional medications, as well as interventions like neuromodulation.