The hemodynamic effects of hypotensive drugs in man. IV. 1-Hydrazinophthalazine.

Further data are presented concerning the unusual hemodynamic effects of 1 -hiydraziniophthalazine. Previous observations demonstrating a marked increase in cardiac output in noimotensive subjects are confirmed in hypertensive patients. The splanchnic vascular bed is one of the sites of increased blood flow. The similarity between the hemodynamic effects of 1-bydr.azinophthalazine and pyirogens is pointed out and the pharmacologic basis for the clinically observed additive effects of 1-1yd)rdazinol)lpthalazine an(d hexamethonium is (liscusse(l.