The spurious increase in serum catecholamine levels associated with methyldopa treatment can be reduced by the simultaneous administration of phenobarbitone. This accelerating effect of phenobarbitone on methyldopa metabolism has been demonstrated in relation to both adrenaline and noradrenaline, and investigations suggest that it is due to the effect of barbiturate on the activity of metaboliz...

1. A within-patient comparison showed that bethanidine, methyldopa and propranolol produced similar control of the blood pressure. 2. Unlike bethanidine, propranolol did not produce postural and exercise hypotension; methyldopa was intermediate in effect. 3. Overall side effects were of a similar incidence though there were differences in incidence of particular side effects.

Methyldopa, an antihypertensive, is a very close analogue of DOPA. Drug interaction accompanied by degradation in a banana juice mixture was reported for DOPA. However, the effect of banana on methyldopa has not been reported. Therefore, we have investigated the impact of banana juice on methyldopa. The drug and supernatant of banana pulp were mixed, and the mixture was observed for changes in ...

1. The fate of orally administered (14)C-labelled l-alpha-methyldopa has been examined in three normal men and in eight hypertensive patients who responded to the drug and three who did not. 2. The output of (14)C in the urine in 2 days and in the faeces in 4 days was not very different in any of the subjects. The normals excreted about 40% of the dose in the urine and 60% in the faeces, the re...

We describe a chromatographic method, in which 3,4-dihydroxybenzylamine is used as the internal standard, for determining free methyldopa in human urine. The drug was adsorbed onto alumina, eluted, and the eluate directly injected onto a reversed-phase column (octadecyl-bonded silica stationary phase), with dilute acetate buffer (pH 2.7) as the mobile phase and ultraviolet detection at 280 nm f...

The effect of regression of left ventricular hypertrophy (LVH) on ventricular performance was studied in two-kidney, one clip Goldblatt hypertensive rats (2K1C) treated with methyldopa or by unclipping. Sham operations were performed in a total of 21 rats; 12 and nine were studied after 4 and 6 weeks, respectively. Hypertension was induced in 38 additional rats. Of these, 11 were studied at 4 w...

The administration of methyldopa (200 mg/kg i.p.) induced a green fluorescence typical of catecholamine fluorescence, in regions of the brain stem which coincided with all the major serotonin cell groups, including the B1, B2, and B3 cell groups in the medulla. Prior administration of 5,7-dihydroxytryptamine (5,7-DHT), a neurotoxin relatively specific for serotonin neurons, prevented the appear...

The interaction between methyldopa and levodopa was studied in 18 patients with Parkinsonism. Together they produced a fall in blood pressure in doses which when given alone had no effect or only a slight hypotensive effect. Severe hypotension never occurred. It is reasonable to give methyldopa to hypertensive patients on levodopa but the regimen should be initiated in hospital.

INTORDUCTION Methyldopa is (2S)-2-amino-3-(3, 4dihydroxyphenyl)-2-methylpropanoic acid (figure1a). Hydrochlorothiazide is 6-chloro-1, 1-dioxo-3,4dihydro-2H-1,2,4-benzothiadiazine-7-sulfonamide (figure1b). Methyldopa and Hydrochlorothiazide are official in Indian Pharmacopoeia and U.S. Pharmacopoeia, but there is no official method for the combination. Both drugs in combination of tablet dosage ...