On entering the stomach alcohol causes the gastric blood-vessels to dilate. Absorption is rapid, the maximum amount being present in the blood about fifteen minutes after ingestion. Once in the blood alcohol produces a dilatation of the cutaneous arterioles, thus diverting a large quantity of blood to the surface of the body and giving rise to a feeling of warmth. This is especially noticeable in the hands and feet, should these have been cold previously. In some alcohol is liable to cause flushing of the face, and, if freely indulged in, it may in such subjects lead to a permanent dilatation of the vessels of the cheeks and nose, at the same time predisposing to acne rosacea. The latter affection, however, it should in justice be observed, is not infrequently met with in the strictly temperate, just as, contrariwise, inveterate drinkers may retain pale faces.
By diverting a large quantity of blood to the surface of the body alcohol tends, while producing a temporary sensation of warmth, to reduce the body temperature. A lowering of several degrees may in this way be effected; the lowest body temperatures met with in the living subject have, in fact, occurred in the drunken. It is largely for this effect that alcohol is employed in febrile states. It may sometimes be given with advantage as a preliminary to the cold bath when the superficial vessels are strongly contracted, for it relaxes these and thus promotes the cooling of the blood by the bath.
Seeing that alcohol dilates the cutaneous vessels, those who are exposed to great cold should abstain from it. This fact has long been recognized by the inhabitants of cold regions and by arctic explorers; for them alcohol spells death. Nansen would not allow a single drop of alcohol in his expeditions, not even for medicinal purposes. It is probable that most of the cases of death from cold recorded in the newspapers would be more correctly described as deaths from drink : a man falls down drunk on a cold night and sleeps his drunken sleep for the last time; under the influence of the alcohol his temperature is lowered beyond the point compatible with life.
Large doses of alcohol paralyse the heart. Smaller doses may cause an increased frequency of the beat, in part reflexly, by stimulating the gastric mucous membrane, and in part, perhaps, by acting directly upon the nerves and muscle of the heart itself. Alcohol can hardly, however, be said to be a genuine cardiac stimulant under normal conditions, though in fainting and in debilitated states of the body it may act as such.