BACKGROUND AND PURPOSE To evaluate the ability of cannabidiolic acid (CBDA) to reduce nausea and vomiting and enhance 5-HT1A receptor activation in animal models. EXPERIMENTAL APPROACH We investigated the effect of CBDA on (i) lithium chloride (LiCl)-induced conditioned gaping to a flavour (nausea-induced behaviour) or a context (model of anticipatory nausea) in rats; (ii) saccharin palatability in rats; (iii) motion-, LiCl- or cisplatin-induced vomiting in house musk shrews (Suncus murinus); and (iv) rat brainstem 5-HT1A receptor activation by 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) and mouse whole brain CB1 receptor activation by CP55940, using [ 35S]GTPgS-binding assays. KEY RESULTS In shrews, CBDA (0.1 and/or 0.5 mg·kg-1...