BD1031 or (R)-2-[2-(3,4-dichlorophenyl)ethyl]octahydropyrrolo[1,2-a]pyrazine is a selective sigma receptor agonist, with a reported binding affinity of Ki = 1 ± 0.2 nM for the sigma-1 receptor and 80 times selectivity over the sigma-2 receptor. The enantiomer of BD1031 is known as BD1018. Consistent with other reported sigma receptor agonists, BD1031 increases the behavioural toxicity of cocaine in Swiss Webster mice.