Figure 2. Effect of daily administration of Cannabis sativa extract on the duration of catalepsy (sec) induced by haloperidol administration over 18 days in mice. Data showed the duration of catalepsy on day 1, 3, 9, 15 and 18 of treatment. Columns 1-4 represent haloperidol control, haloperidol + cannabis 5, 10 or 20 mg/kg, respectively. Asterisks indicate significant change from the haloperidol control group. Cannabis given to saline treated mice failed to induce catalepsy (not shown).