Cannabidiol (CBD) is protective against increased permeability of the BBB associated with oxygen–glucose derivation (OGD). The effects of CBD given before (A), immediately after (B) OGD, or 2 h (C) or 4 h (D) into the reperfusion period on TEER values. Data are given as mean ± SEM (n represents the total number of inserts measured, based on three to four separate experiments). Statistical analysis was conducted by two‐way anova with post hoc analysis at each time point comparing data against the vehicle control. *P < 0.05, **P < 0.01, ***P < 0.001; 10 μM CBD versus vehicle. # P < 0.05, ## P < 0.01, ### P < 0.001, 1 μM CBD versus vehicle, + P < 0.05, ++ P <0.01`, +++ P <, 0.001, 100 nM CBD versus vehicle.