Methyldopa is known to cause the production of autoantibodies against red blood cells (RBCs), leading to a positive direct antiglobulin test (DAT) and hemolytic anemia. In about 20% of patients taking methyldopa, IgG autoantibodies develop against RBCs. However, most of the patients do not have hemolysis. A small percentage of such DAT-positive patients, about 2% of those taking methyldopa, dev...

Chemical stimulation of brain cholinergic neurons in many species can produce hypertension. Recent studies in this laboratory have demonstrated that clonidine inhibits this central cholinergic pressor response by inhibiting the biosynthesis of brain acetylcholine. This study was designed to determine whether methyldopa, like clonidine, could inhibit brain cholinergic neurons involved in cardiov...

a-Methyldopa significantly lowered mean blood pressure and plasma renin activity in dogs anesthetized with sodium pentobarbital. After unilateral ligation of the right renal vessels and contralateral denervation of the kidney, a-methyldopa significantly lowered mean blood pressure but did not change plasma renin activity. It was concluded that a-methyldopa acutely lowers plasma renin activity v...

A new, simple, precise, rapid and low-cost spectrophotometric method for methyldopa determination in pharmaceutical preparations is described. This method is based on the complexation reaction of methyldopa with molybdate. Absorbance of the resulting yellow coloured product is measured at 410 nm. Beer’s Law is obeyed in a concentration range of 50 – 200 μg ml methyldopa with an excellent correl...

Growth of Knowledge in the Nineteenth Century, 2742 The Measurement of Blood Pressure, 2743 Forerunners of Modern Treatment, 2743 Low-Salt Diets, 2743 Surgical Sympathectomy, 2744 The Beginnings of Drug Treatment, 2744 Ganglion-Blocking Drugs, 2745 Veratrum Viride, Hydrazaline, and Reserpine, 2746 The Modern Era of Antihypertensive Drugs, 2747 Thiazide Diuretics, 2747 Guanethidine and Alpha-Met...

Effective antihypertonsive drug therapy began with the ganglion-blocking agents, followed by reserpine and hydralarine. later advances included the benzothiadiazine saluretic agents and more recently compounds which specifically inhibit the sympathetic nervous system, such as guanethidine, alpha-methyldopa, and certain amine oxidase inhibitors. Among the antihypertensive drugs, molecular modifi...

This study of guanfacine in 27 patients suffering from moderate-to-severe hypertension showed a satisfactory blood pressure control in 26 patients. Twenty-one of the 27 patients completed a one-year clinical trial with good blood pressure response. The new drugs, acting through the stimulation of the central alpha-adrenoceptors, are useful in patients suffering from moderate-to-severe hypertens...

Isometric exercise causes a substantial rise in BP in normotensive and untreated hypertensives. The authors studied the isometric hand-grip test in 5 groups of treated hypertensives, namely beta-blockers, beta-blockers + diuretics, beta-blockers + diuretics + vasodilators, alpha-methyldopa alone and labetalol. All groups showed a substantial rise in both systolic and diastolic BP, and the incre...