Abstract Rationale Cannabidiol (CBD) and cannabidiolic acid (CBDA) are non-psychoactive components of the cannabis plant. CBD has been well characterised to have anxiolytic and anticonvulsant activity, whereas the behavioural efects of CBDA are less clear. Preclinical and clinical data suggests that CBD has antipsychotic properties and reduces methamphetamine selfadministration in rats. An animal model that is commonly used to mimic the neurochemical changes underlying psychosis and drug dependence is methamphetamine (METH) sensitisation, where repeated administration of the psychostimulant progressively increases the locomotor efects of METH. Objective The aim of this study was to determine whether CBD or CBDA attenuate METH-induced sensitisation of locomotor hyperactivity...