This paper synthesizes recent evidence on the differential contribution of drug classes to impulsive behaviors in patients with substance use disorder. It focuses on delineating which domains of impulsivity vary by substance class, which impulsivity dimensions predict treatment outcomes, and the principal neurobiological findings. Recent studies report elevated impulsivity across most substance use disorders with substance-specific patterns. Stimulants, particularly methamphetamine, produce the most pervasive deficits in inhibitory control, planning, and decision-making. Alcohol and opioids are associated with broad decision-making impairments and elevated trait impulsivity that often persist during substitution treatments. By contrast, cannabis shows the weakest and most inconsistent effects. Impulsive decision-making consistently predicts relapse. Neuroimaging implicates frontostriatal circuits, the insula, and the cingulate cortex, with substance-specific differences in regional volume, receptor availability, and network connectivity. Genetic evidence is limited and heterogeneous. Impulsivity is a transdiagnostic marker with substance-specific profiles that influence both relapse risk and treatment response. Longitudinal, comparative, and network-focused studies employing consensus measures are needed to clarify causality and inform personalized interventions.
Díaz-López et al. (Mon,) studied this question.