The scope of the problem of senile and arteriosclerotic brain syndromes is suggested by population and state hospital statistics. Between 1900 and 1950 the population of the United States doubled, while the number of persons aged 65 or over increased fivefold. Presently, 30% of the patients in state mental hospitals are over 65; of this group 41% are senile-arteriosclerotic. Nearly one third (27%) of all first admissions are over 65; of these over 80% are senile-arteriosclerotic.2
Because of the assumption that arteriosclerotic patients would benefit from improved cerebral circulation, vasodilators such as tolazoline hydrochloride (Priscoline) and 3-pyridinemethanol (Roniacol, the alcohol corresponding to nicotinic acid) have had extensive clinical use. That these agents actually do not increase cerebral blood flow has been established.12
Recent work with the vasodilating agent isoxsuprine hydrochloride (Vasodilan) demonstrated its effectiveness in increasing cerebral blood flow.5 A recent study of this drug 1 indicated