-
American Heart Journal Nov 1983Data are presented on 22 hypertensive patients in an 18-week, double-blind comparison of trimazosin and methyldopa during which treatment with polythiazide was... (Clinical Trial)
Clinical Trial Comparative Study
Data are presented on 22 hypertensive patients in an 18-week, double-blind comparison of trimazosin and methyldopa during which treatment with polythiazide was continued. Maximum daily doses of trimazosin and methyldopa were 800 and 2000 mg, respectively. Eight of nine patients receiving trimazosin and 8 of 12 receiving methyldopa had excellent or good overall responses. (One trimazosin patient was not evaluated for overall response.) Quantitative criteria of blood pressure response indicated that trimazosin was as effective as methyldopa. There were no clinically significant changes in results of Holter monitor recordings, ECGs, chest x-ray films, cardiopulmonary tests, or ophthalmoscopy. There were no abnormalities in laboratory tests of trimazosin patients. One patient receiving methyldopa had a positive Coombs' test. Significant side effects developed in two methyldopa patients-syncope in one patient and postural hypotension in the other. No significant side effects occurred in the patients taking trimazosin.
Topics: Adult; Antihypertensive Agents; Blood Pressure; Clinical Trials as Topic; Double-Blind Method; Drug Therapy, Combination; Female; Humans; Hypertension; Male; Methyldopa; Middle Aged; Piperazines; Polythiazide
PubMed: 6356853
DOI: 10.1016/0002-8703(83)90184-9 -
ZFA. Zeitschrift Fur Allgemeinmedizin Jul 1983
Topics: Antihypertensive Agents; Drug Combinations; Female; Humans; Hypertension; Long-Term Care; Male; Polythiazide; Prazosin; Quinazolines
PubMed: 6412473
DOI: No ID Found -
Clinical Pharmacology and Therapeutics Jun 1983M-mode echocardiography has become a valuable tool in the evaluation of changes in left ventricular muscle mass during antihypertensive therapy. We evaluated the effects...
M-mode echocardiography has become a valuable tool in the evaluation of changes in left ventricular muscle mass during antihypertensive therapy. We evaluated the effects of treatment with the vasodilator trimazosin, alone and in combination with the diuretic polythiazide, on cardiac muscle mass in hypertensive subjects. Trimazosin alone was given to 11 subjects for 18 mo, and average supine blood pressure fell from 154/100 to 146/89 mm Hg. Heart rate and body weight did not change during therapy. Initially, a slight decrease (approximately 6%) was observed in left ventricular muscle mass, but left ventricular transverse dimension and left ventricular muscle mass returned to control levels during the last 6 mo of the 18-mo study. The combination of trimazosin and polythiazide was given to nine subjects and decreased blood pressure from 152/102 to 138/92 mm Hg. Heart rate increased and body weight decreased slightly. No changes in left ventricular muscle mass were observed during combination therapy. It is possible that increases in activity of the sympathetic nervous system during therapy with trimazosin alone, and the observed increase in renin activity during treatment with trimazosin and polythiazide, might have offset the effects of the reduction in blood pressure on left ventricular muscle mass.
Topics: Adult; Aged; Blood Pressure; Body Weight; Cardiomegaly; Drug Evaluation; Drug Therapy, Combination; Echocardiography; Heart Rate; Humans; Hypertension; Male; Middle Aged; Muscle, Smooth, Vascular; Piperazines; Polythiazide
PubMed: 6221856
DOI: 10.1038/clpt.1983.99 -
MMW, Munchener Medizinische... Jul 1982
Topics: Adrenergic alpha-Antagonists; Adult; Antihypertensive Agents; Blood Pressure; Circadian Rhythm; Drug Combinations; Female; Humans; Hypertension; Male; Middle Aged; Polythiazide; Prazosin; Quinazolines
PubMed: 6126809
DOI: No ID Found -
Clinical Pharmacology and Therapeutics May 1982Trimazosin was given for periods of at least 6 mo to 25 patients with mild to moderate essential hypertension. In doses of 300 to 900 mg dialy trimazosin alone led to...
Trimazosin was given for periods of at least 6 mo to 25 patients with mild to moderate essential hypertension. In doses of 300 to 900 mg dialy trimazosin alone led to blood pressure control (supine diastolic blood pressure less than 90 mm Hg with a fall of at least 10 mm Hg) in 16 patients (64%). Despite the decrements in blood pressure there were no changes in body weight or creatinine clearance. There was also no changes in plasma renin activity or urinary aldosterone excretion rate. Although patients with high control renin values appeared to have greater blood pressure decreases than those with low renin values, responsiveness to treatment was not associated with consistent effects of trimazosin on the renin-angiotensin system. Trimazosin induced a small decrease in plasma total cholesterol concentration. In seven patients whose blood pressures were not controlled by trimazosin alone, the addition of polythiazide led to decreased blood pressure and in five control of pressure was achieved. Thus, trimazosin is an effective antihypertensive when given by itself or in combination with a diuretic. Its mechanism of action has not been established, but its ability to induce vasodilation without concomitant sodium retention or stimulation of the renin axis may be an important factor in its effectiveness.
Topics: Adult; Aged; Aldosterone; Antihypertensive Agents; Blood Pressure; Body Fluids; Female; Heart Rate; Humans; Hypertension; Male; Middle Aged; Piperazines; Renin; Time Factors
PubMed: 7042174
DOI: 10.1038/clpt.1982.80 -
JPMA. the Journal of the Pakistan... Feb 1982
Topics: Adult; Aged; Drug Combinations; Female; Humans; Hypertension; Male; Middle Aged; Polythiazide; Prazosin; Quinazolines
PubMed: 6803002
DOI: No ID Found -
Biopharmaceutics & Drug Disposition 1982An assay was developed for benzthiazide in plasma, urine and feces, using high performance liquid chromatography (HPLC). A reverse-phase column was employed, with...
An assay was developed for benzthiazide in plasma, urine and feces, using high performance liquid chromatography (HPLC). A reverse-phase column was employed, with quantitation af 280 nm, using polythiazide as an internal standard. In three of four human subjects who received a 50 mg benzthiazide tablet the plasma concentrations were below the 10 ng ml-1 sensitivity limit of the assay, and the urinary recovery averaged less than one per cent of the dose. One subject received a 50 mg dose as both a tablet and a solution; the urinary recoveries for these two doses were 1.7 and 10.4 per cent, respectively. Fecal samples, obtained from two subjects who received 50 mg tablets, were estimated to contain approximately 80 per cent of the administered dose.
Topics: Adult; Benzothiadiazines; Chromatography, High Pressure Liquid; Diuretics; Feces; Half-Life; Humans; Male; Sodium Chloride Symporter Inhibitors
PubMed: 7082774
DOI: 10.1002/bdd.2510030102 -
Journal of Chromatography Jun 1981A selective high-performance liquid chromatographic method has been developed for the determination of polythiazide in human plasma down to concentrations of 0.5 ng/ml....
A selective high-performance liquid chromatographic method has been developed for the determination of polythiazide in human plasma down to concentrations of 0.5 ng/ml. Polythiazide and an internal standard (epithiazide) are simultaneously extracted from the sample, the extract is purified on a silica micro-column and analyzed on a muBondapak CN column. Chloroform-methanol (97:3) is the eluent, with spectrophotometric detection at 264 nm. The extraction methodology developed for the analysis of polythiazide in blood plasma allows the simultaneous quantitative determination of prazosin, which is frequently administered together with thiazide diuretics. The precision and accuracy of both the polythiazide and the prazosin assays are excellent and are not seriously affected by the simultaneous presence of both drugs in the plasma. Therefore, determination of polythiazide and prazosin is possible using a single plasma sample.
Topics: Chromatography, High Pressure Liquid; Humans; Polythiazide; Prazosin; Quinazolines
PubMed: 7263818
DOI: 10.1016/s0378-4347(00)80135-8 -
Ugeskrift For Laeger Jan 1981
Topics: Aged; Alkalosis; Female; Furosemide; Humans; Hypokalemia; Polythiazide
PubMed: 7210227
DOI: No ID Found -
Nephron 1981The physiologic action of prazosin in man was studied in 23 patients including 10 treated with prazosin plus polythiazide. Responders to prazosin alone (blood pressure...
The physiologic action of prazosin in man was studied in 23 patients including 10 treated with prazosin plus polythiazide. Responders to prazosin alone (blood pressure fell greater than 10 mm Hg) had a decrease in peripheral resistance (p less than 0.02) and no significant change in plasma volume, while nonresponders' plasma volume rose significantly (p less than 0.02). 10 patients treated with prazosin and polythiazide (blood pressure not normalized on prazosin alone) were analyzed at baseline (Rx 0), after prazosin (Rx 1), and after prazosin plus polythiazide (Rx 2). Mean supine blood pressure fell from 184/118 +/- 8/5 (SE) mm Hg at Rx 0 to 161/106 +/- 7/4 mm Hg at Rx 1 (p less than 0.005) and 129/89 +/- 4/4 mm Hg at Rx 2 (p less than 0.001). Supine renin increased in each group, but the increase with prazosin alone was not significant. Stimulated renin activity increased significantly after Rx 2 (p less than 0.0025). Cardiac output fell, plasma volume returned to baseline values, and peripheral resistance fell by 467 dyn s/cm-5 during thiazide treatment (p less than 0.025).
Topics: Adult; Blood Pressure; Cardiac Volume; Drug Combinations; Female; Hemodynamics; Humans; Hypertension; Male; Middle Aged; Plasma Volume; Polythiazide; Prazosin; Quinazolines; Renin-Angiotensin System; Vascular Resistance
PubMed: 7329480
DOI: 10.1159/000182245