The parameters of the general and cerebral hemodynamics were studied in 36 patients with chronic insufficiency of the cerebral circulation following papaverine administration. In patients with the early stages of the disease, papaverine elicited a decrease in the arterial pressure and the peripheral resistance to the blood flow. The amplitude of the rheographic curve increased significantly two minutes after the intravenous injection of papaverine. Papaverine is recommended for patients with the compensatory and remitting stages of the disease. In latent cardiovascular insufficiency, papaverine should be combined with cardiogenic agents and drugs promoting metabolism in the cardiac muscle.