Drugs that stimulate brain 2 receptors included methyldopa, clonidine, guanabenz, and guanfacine. The main side effect of this class of drugs is sleepiness. Hydrazine Hydralazine is the only presently used drug in this class. It is a potent drug that acts directly to relax the smooth muscle cells in the walls of arteries, causing arterial dilatation and a brisk reduction in blood pressure. Successful use of this drug usually requires aggressive dosing and because of the drugs rapid metabolism, it must be given three to four times daily.
Fluid retention is commonplace as is tachycardia.
Angiotensin II is one of the most potent naturally occurring constrictors of arteries in the body and is intimately involved in blood pressure regulation. I. This step requires the action of an enzyme - Renin, which is manufactured by the kidneys. Any drug that interferes with the production or activity of angiotensin II will lower blood pressure. All beta blockers reduce the production of renin by the kidneys and thus secondarily reduce angiotensin production. ACE inhibitors are remarkably effective antihypertensive drugs and they have also been shown to reduce mortality after heart attacks and to reduce heart enlargement after heart attacks.