Chronic effects of metoprolol and methyldopa on calf blood flow in intermittent claudication. Methyldopa and propranolol or practolol in moderate hypertension. A multicenter, double-blind, randomized, placebo-controlled study of isradipine and methyldopa as monotherapy or in combination with captopril in the treatment of hypertension. The LOMIR-MCT-IH Research Group. Haemodynamic changes in peripheral arterial circulation during antihypertensive treatment with captopril, methyldopa and indapamide. Comparison of trimazosin and methyldopa in hypertension. Prazosin in hypertension: a double-blind evaluation with methyldopa and placebo. Antihypertensive efficacy of alpha-methyldopa, chlorothiazide and Supres-150 (alpha-methyldopa-chlorothiazide). Effects of methyldopa on psychometric performance.
In a placebo-controlled double-blind study 14 hypertensive patients with intermittent claudication were treated with metoprolol (100-200 mg daily) and methyldopa (500-1000 mg daily) for 3 weeks and their effects on heart rate, blood pressure as well as on resting and hyperaemic calf blood flow and vascular resistance were compared. In their antihypertensive effect metoprolol and methyldopa did not differ significantly. In 23 diseased limbs the calf blood flow and vascular resistance remained unchanged at rest during the trial. The active drugs reduced hyperaemic flow (P less than 0.05). The peak flow was reduced by 20% (P greater than 0.01) with metoprolol and by 15% with methyldopa below the initial level and by 17% and by 12% below the level recorded on placebo, respectively. Neither of the drugs influenced vascular resistance during reactive hyperaemia. Thus, in patients with intermittent claudication antihypertensives should be used with care. The effect of a low dose of methyldopa combined with (a) a non-selective and (b) a selective beta-adrenoceptor antagonist was studied in a double-blind crossover trial in 24 carefully selected patients with moderate hypertension (mean initial lying blood pressure 189/117 mm Hg). Each patient received methyldopa 750 mg/day, propranolol 240 mg/day, practolol 600 mg/day, methyldopa 750 mg/day combined with propranolol 240 mg/day, methyldopa 750 mg/day combined with practolol 600 mg/day, and placebo for four weeks each according to a random sequence. After four weeks of therapy the most effective treatment, methyldopa combined with propranolol, reduced lying and standing blood pressures by 36-5/21-4 mm Hg and 44-7/25 mm Hg respectively. Thic combination had similar effects to those of the combination of methyldopa with the cardioselective agent practolol except that it reduced lying diastolic pressure further. The combination was more effective than either treatment alone. No significant differences were found between the effects of propranolol, practolol, or methyldopa at the doses used. This multicenter, double-blind, randomized trial of 1 year's duration compared the safety and efficacy of isradipine, methyldopa, and placebo in 368 men, aged 40 to 65 years, with mild-to-moderate essential hypertension. Initial treatment with isradipine (1.25 mg twice daily), methyldopa (250 mg twice daily), or placebo was started after a wash-out and single-blind placebo period. If normotension [diastolic blood pressure (DBP) < 95 mm Hg] was not achieved, doses were doubled. If the maximum dose as monotherapy did not result in normotension, captopril (25 mg or, if necessary, 50 mg, once daily) was added to the treatments of the three patient groups. Despite the marked placebo effect during the first 2 weeks of treatment, monotherapy with isradipine resulted in a higher rate of normalization (more than 64%) compared with 50% in the methyldopa group and 36% in the placebo group. Adding captopril to the treatments of non-responders increased the rate of normalization to 90% in the isradipine group, 84% in the methyldopa group, and 75% in the placebo group. Twenty-one patients dropped-out and 70 patients discontinued the study, the majority because of a lack of efficacy and adverse reactions. The most common adverse reactions reported were cardiovascular and gastrointestinal complaints, headaches, and sleep and sexual disorders, mostly by patients taking methyldopa. Isradipine was well tolerated and the side-effects were minimal. These results indicate that isradipine is superior to methyldopa and, whether as monotherapy or in combination with captopril, highly effective and well tolerated in the treatment of mild-to-moderate hypertension. Structural changes in resistance vessels of the lower limbs have been detected in early stages of arterial hypertension. In these patients it might be important to reduce blood pressure by drugs which do not impair peripheral blood flow. Twenty-four patients with arterial hypertension, without target organ damage were randomly given a placebo, 50 mg captopril, 500 mg methyldopa or 2.5 mg indapamide and their blood pressure, arterial blood flow and peripheral resistance were measured at baseline and at the peak action of the antihypertensive treatment. Significant decreases in blood pressure and peripheral resistance have been induced by a single oral dose of captopril and methyldopa: a concomitant significant increase in peripheral blood flow to the lower limbs was also observed during methyldopa treatment. No acute effect was observed on the placebo or on indapamide: the latter induced a decrease in blood pressure and in peripheral resistance along with an increase in arterial blood flow during long-term treatment after four weeks of therapy. Our observations seem to support the usefulness in hypertensive patients with concomitant lesions in the peripheral arterial tree of antihypertensive agents such as methyldopa and indapamide which increase blood flow and reduce peripheral resistance while lowering high blood pressure. Eighteen patients with hypertension participated in a double-blind, randomized study to evaluate the effect of trimazosin, methyldopa, and placebo on supine and standing blood pressure and heart rate. Of 6 patients on methyldopa, one developed drug fever (and was dropped from the study) and one developed impotence. None of 6 patients on trimazosin and none of 6 patients on placebo developed any adverse effects. The mean supine blood pressure on 900 mg trimazosin daily was 17.0/12.8 mm Hg lower than that on the first placebo trial (p less than 0.01) and 17.0/12.1 mm Hg lower than that on the second placebo trial (p less than 0.01). The mean supine blood pressure on 2,250 mg methyldopa daily was 17.8/12.4 mm Hg lower than that on the first placebo trial (p less than 0.01) and 16.8/13.0 mm Hg lower than that on the second placebo trial (p less than 0.01). The mean supine blood pressure was not significantly affected by placebo. Trimazosin, 900 mg daily, and methyldopa, 2,250 mg daily, were equally effective in lowering supine and standing systolic and diastolic blood pressure and did not affect supine or standing heart rate. nan Twenty-two white men and two white women with uncomplicated essential hypertension participated in a randomized double-blind trial comparing placebo with alpha-methyldopa (750 mg/d orally) and chlorothiazide (450 mg/d orally), alone or in combination. There were no significant differences in blood pressures as measured with the patients lying down; however, with the patients standing the systolic, diastolic and mean arterial blood pressures were significantly lower (P < 0.05) after treatment with alpha-methyldopa or the combination product. The higher the blood pressure before treatment, the greater the fall with treatment. Adverse effects were infrequent. Double-blind, crossover comparisons of methyldopa with placebo were performed in 16 patients with mild to moderate hypertension. Methyldopa (250 mg tid) for 14 days significantly reduced blood pressure, impaired card-sorting time and digital symbol substitution score, and caused trends for impairment of other psychometric tests. Effects of practice were greater than those of treatment on all tests other than card sorting, although no interaction between treatment and practice was seen. Continued dosage impairs psychometric performance, but practice effect is a major confounder. Simple crossover studies are inadequate for detecting moderate drug effects on intellectual performance.