Assessment of adverse effects of neurotropic drugs in monkeys with the “Drug Effects on the Nervous System” (DENS) scale

► We described a new scale to assess adverse drug effects on the nervous system in primates. ► We compared the new scale with a classic motor scale. ► Behavioural data were temporally correlated to the projected receptor occupancy. ► The new scale is accurate and sensitive to assess common side effects of neurotropics.