Background: The phytocannabinoid cannabidiol (CBD) exhibits antioxidant and antiinflammatory properties. The present study was designed to explore its effects in a mouse model of sepsis-related encephalitis by intravenous administration of lipopolysaccharide (LPS). Methods: Vascular responses of pial vessels were analyzed by intravital microscopy and inflammatory parameters measured by qRT-PCR. Results: CBD prevented LPS-induced arteriolar and venular vasodilation as well as leukocyte margination. In addition, CBD abolished LPS-induced increases in tumor necrosis factor-alpha and cyclooxygenase-2 expression as measured by quantitative real time PCR. The expression of the inducible-nitric oxide synthase was also reduced by CBD. Finally, preservation of Blood Brain Barrier integrity was also associated to the treatment with CBD. Conclusions: These data highlight the antiinflammatory and vascular-stabilizing effects of CBD in endotoxic shock and suggest a possible beneficial effect of this natural cannabinoid.