Certain 1,5-disubstituted benzimidazol-2-one compounds useful as therapeutic agents. The compounds may be of the Formula I ##STR00001## wherein: R' represents hydrogen or alkyl; R'' represents halogen or trihalogenmethyl; and Hlg represents halogen; provided, however, that if Hlg is F, then R'' is not Cl. Also, use of the 1,5-disubstituted benzimidazol-2-one compounds, or pharmaceutically-acceptable addition salts thereof, in applications that benefit from increasing the blood-brain barrier permeability.