Rheohepatographic [correction of Rheoencephalographic] investigations were performed in 60 smokers and 30 non-smoking (control group) apparently healthy male subjects aged between 23-32 years. Those persons with "length" of smoking habit for up to 5 years presented with hyper-reactivity of arterial and venous vessels, reduction in the liver [correction of brain] pulse filling. In prolonged and continuous users of tobacco (with the smoking history ranging from 6 to 10 years inclusive) there has been noted a general tendency towards reduction in hyper-reactivity of vessels, particularly small ones. The tone of medium and large vessels decreased to a lesser extent. Further tendency toward reduction in the liver [correction of brain] pulse filling has been taken note of.