Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0085580 (essential hypertension)
 14,686 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The present study, undertaken in general practice, was designed to evaluate the effects of age on the pharmacodynamics and pharmacokinetics of a conventional and a slow-release formulation (Securon SR) of verapamil. Two groups of 12 patients with essential hypertension were treated in an open, randomized, crossover study. One group was younger than 65 years, mean 58 (range 50-64 years) and the other was 65 years and older, mean 72 (range 66-77 years). The patients were titrated through three steps with the two different formulations to efficacy or to maximal dosage. During a 4-week drug-free run-in period the mean blood pressures were 167 +/- 14/103 +/- 4, 168 +/- 18/105 +/- 6, and 168 +/- 18/105 +/- 5 mm Hg at 0, 2, and 4 weeks, respectively, for the whole group. The final blood pressure at control showed a fall with sustained-release verapamil for systolic blood pressure (SBP) and diastolic blood pressure (DBP) of 15 +/- 16 and 17 +/- 5 mm Hg for the younger group and 14 +/- 16 and 14 +/- 6 mm Hg for the older group. For the conventional formulation the falls of SBP and DBP were 14 +/- 18 and 18 +/- 8 mm Hg for the younger group and 19 +/- 16 and 13 +/- 9 mm Hg for the older group. There were no significant differences between the responses to the two formulations nor between the two age groups. The pharmacokinetics of both formulations were investigated at steady state and no significant effects of age were observed. However, there were significant differences between the time-concentration profiles for the formulations. These findings suggest that there are no significant effects of age on the pharmacodynamics and pharmacokinetics of verapamil.
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PMID:The effects of age on the pharmacodynamics and pharmacokinetics of two formulations of verapamil. 247 90

To study the relation of calcium channel blockade to calcium metabolism, we measured serum ionized calcium (Ca++i0), magnesium (Mg), calcitonin (CT), and 1,25-dihydroxyvitamin D (1,25-D) before and after short-term therapy with verapamil 120 mg three times daily in essential hypertensive subjects on low (10 mEq) and high (200 mEq) dietary sodium intakes. Salt-sensitive compared with salt-insensitive subjects on high v low dietary salt intake had lower Ca++i0 (P less than .05), higher 1,25-D (P less than .02), and a greater hypertensive responsive to verapamil (% delta DBP = 17.7 v -8.2, P less than .05). The % delta DBP was related to the initial CT (r = 0.68, P less than .05), initial 1,25-D (R = -0.89, P less than .01), and to the drug-induced % delta 1,25 D (R = .60, P less than .05). Thus, lower initial calcium and calcitonin levels, higher initial levels of 1,25-D, and a greater drug-induced suppression of 1,25-D were associated with an enhanced hypotensive response to verapamil. Verapamil elevated Ca++i0 (2.46 +/- 0.04 to 2.53 +/- 0.04 2.00 mEq/L, P less than .05), and suppressed Mg (2.00 +/- 0.03 to 1.84 +/- 0.03 mEq/L, P less than .01) and 1,25-D levels (66.7 +/- 8.1 to 51.6 +/- 5.7 pg/mL, P less than .05). These results suggest interactive effects of sodium and calcium metabolism in essential hypertension, especially among salt-sensitive individuals. We conclude that alterations of calcium metabolism may underlie the sensitivity to verapamil therapy and may contribute to its hypotensive effects.
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PMID:The effects of calcium channel blockade on blood pressure and calcium metabolism. 261 Sep 99

Although verapamil is a well-established treatment for angina, cardiac arrhythmias and cardiomyopathies, this review reflects current interest in calcium antagonists as anti-hypertensive agents by focusing on the role of verapamil in hypertension. Verapamil is a phenylalkylamine derivative which antagonises calcium influx through the slow channels of vascular smooth muscle and cardiac cell membranes. By reducing intracellular free calcium concentrations, verapamil causes coronary and peripheral vasodilation and depresses myocardial contractility and electrical activity in the atrioventricular and sinoatrial nodes. Verapamil is well suited for the management of essential hypertension since it produces generalised systemic vasodilation resulting in a marked reduction in systemic vascular resistance and, consequently, blood pressure. Evidence from clinical studies supports the role of oral verapamil as an effective and well-tolerated first-line treatment for the management of patients with mild to moderate essential hypertension. Clinical studies have shown that verapamil is more effective the higher the pretreatment blood pressure and some authors have found a more pronounced antihypertensive effect in older patients or in patients with low plasma renin activity. Sustained release verapamil formulations are available for oral administration which, as a single daily dose, are as effective in lowering blood pressure over 24 hours as equivalent doses of conventional verapamil formulations given 3 times daily. As a first-line antihypertensive agent, oral verapamil is equivalent to several other calcium antagonists, beta-blockers, diuretics, angiotensin-converting enzyme (ACE) inhibitors and other vasodilators, and is not associated with many of the common adverse effects of these treatments. Verapamil may be preferred as an alternative first-line antihypertensive treatment to diuretics in elderly patients because it has similar efficacy in these patients without causing the adverse effects commonly linked with diuretic treatment. Furthermore, because verapamil does not cause bronchoconstriction, it may be used in preference to beta-blockers in patients with asthma or chronic obstructive airway disease. Reflex tachycardia, orthostatic hypotension or development of tolerance is not evident following verapamil administration. As a second- or third-line treatment for patients refractory to established antihypertensive regimens, verapamil produces marked blood pressure reductions when combined with diuretics and/or ACE inhibitors, beta-blockers and vasodilators such as prazosin.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Verapamil. An updated review of its pharmacodynamic and pharmacokinetic properties, and therapeutic use in hypertension. 267 May 11

The antianginal and antiarrhythmic role of calcium antagonists is well established. Recent preliminary studies have indicated that, like beta blockers, calcium antagonists may produce short- and long-term hypotensive effects in patients with mild to moderate essential hypertension. The pharmacologic properties of calcium antagonists provide a clear rationale for their use in the control of essential hypertension. The comparative hypotensive effects of verapamil (80 to 160 mg 3 times a day) and propranolol (40 to 120 mg 3 times a day) were evaluated over 4 weeks, preceded by a 4-week placebo phase, in a double-blind protocol in 17 patients with mild to moderate hypertension. Verapamil (n = 10) reduced the mean sitting systolic blood pressure by 10.7% (p less than 0.01) and standing by 7.6% (p less than 0.04). The corresponding data for propranolol (n = 7) were 4.8% (not significant) and 5% (p = 0.04). Verapamil reduced the sitting diastolic blood pressure by 10.8% (p less than 0.01), propranolol by 7.5% (p = 0.01); the standing diastolic blood pressure was reduced by 10.7% with verapamil (p less than 0.01) and by 8.6% (p = 0.01) with propranolol. With verapamil the mean heart rate fell from 77.60 +/- 8.42 to 70.20 +/- 4.85 beats/min (p = 0.03); with propranolol it fell from 76.85 +/- 6.91 to 66.29 +/- 4.54 beats/min (p less than 0.01). Although a trend towards a slightly greater hypotensive effect was apparent with verapamil compared with propranolol, the difference was not statistically significant. It is concluded that verapamil and propranolol exert comparable hypotensive potency in patients with mild to moderate hypertension.
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PMID:Calcium antagonists and beta blockers in the control of mild to moderate systemic hypertension, with particular reference to verapamil and propranolol. 286 76

Verapamil and nifedipine are the most frequently used calcium channel blocking agents in Sweden at present time. The pharmacokinetics of verapamil has been described both in healthy volunteers as well as in patients with supraventricular arrhythmias, angina pectoris, liver cirrhosis, hypertrophic cardiomyopathy or hypertension. Intravenous pharmacokinetics of nifedipine has been investigated in healthy volunteers and oral pharmacokinetics in healthy volunteers as well as in patients with hypertension. The pharmacokinetics of verapamil and of one of its metabolites, norverapamil, is changed after multiple oral dosing as has been described in patients with supraventricular tachyarrhythmias, angina pectoris or in patients with essential hypertension. Plasma concentration-effect relationships have been established for verapamil in different clinical situations and in a few cases also for nifedipine. An update of the pharmacokinetics of these two important calcium channel blocking agents is presented.
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PMID:Pharmacokinetics of calcium channel blocking agents. 294 Jul 99

In a prospective, open study 45 patients (mean age fifty-three years) with essential hypertension were treated with verapamil for four to eight years (mean 5.3 years). Blood pressure was satisfactorily controlled (from 160/104 to 145/91) and the side effects were infrequent, mild, and often transient. Verapamil did not exert any unfavorable metabolic or hematologic effects over the years. HDL-cholesterol was moderately increased (mean 24%) and the other plasma lipids were unaffected. These data suggest that the calcium channel blocker verapamil is a metabolically safe drug to use as monotherapy in essential hypertension.
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PMID:No metabolic side effects of long-term treatment with verapamil in hypertension. 318 48

The effects of verapamil and bendrofluazide used singly and in combination were examined in patients with primary hypertension in a patient blind, partly observer blind placebo controlled study of parallel group design; there were ten subjects in each arm of the trial. Verapamil 160 mg twice daily caused supine mean arterial pressure to fall by 21 mmHg; this reduction was significantly greater (p less than 0.05) than that induced by bendrofluazide 5 mg daily which caused a fall of only 10 mmHg. The addition of verapamil 160 mg twice daily to bendrofluazide 5 mg daily caused a further fall in pressure of 18 mmHg (p less than 0.005), but the reduction in pressure when bendrofluazide was added to verapamil was only 1 mmHg and not significant. Bendrofluazide therapy caused a fall in plasma potassium concentration and an increase in plasma urate concentration; urinary calcium excretion was reduced. Verapamil caused no detectable biochemical alterations in plasma or urine.
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PMID:Verapamil and bendrofluazide in the treatment of hypertension: a controlled study of effectiveness alone and in combination. 329 21

To evaluate the hypotensive efficacy of Verapamil alone and combined with diuretic, in the treatment of essential hypertension in elderly patients, we studied 54 patients, mean age 67.2 +/- 4.7 years, with essential hypertension, I-II WHO class. After a two-week wash-out from previous hypotensive therapies, patients were divided, at random, into three groups and, in double-blind conditions; they were treated as follows: the first group was treated with Verapamil (V) slow-release 240 mg/die, the second group with Chlorthalidone (C) 50 mg/die and the third group with the combination of Verapamil slow-release 240 mg/die and Chlorthalidone 50 mg/die (V + C). In the first group, the therapy (V) statistically reduced (p less than 0.001) either PAS or PAD values in supine position, (respectively -13 +/- 9 mmHg and -12 +/- 4 mmHg) and PAS-PAD values in upright position (respectively -16 +/- 3 mmHg and -10 +/- 3 mmHg). In the group treated with C, a statistically significant reduction (p less than 0.001) of PAS (-12 +/- 3 mmHg in supine position and -16 +/- 3 mmHg in upright position) and of PAD (-11 +/- 5 in supine and -9 +/- 4 mmHg in upright position). In the third group, V + C treatment induced a statistically bigger reduction of PAS and PAD (p less than 0.001) than that of the other two groups either in supine (-24 +/- 3 and -21 +/- 5 mmHg, respectively) or in upright position (-26 +/- 4 and -20 +/- 5 mmHg, respectively). Three patients interrupted the therapy for scarse compliance (I-II group).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Hypotensive efficacy of verapamil alone and in combination with a diuretic in the treatment of essential hypertension in geriatric patients]. 330

The influences of verapamil, propranolol and their combination on blood pressure and heart rate during cold pressor testing and isometric exercise were examined in 13 patients with essential hypertension. Verapamil modified the peak pressor responses to each stimulus while the major action of propranolol was on heart rate. Together the drugs attenuated both haemodynamic responses. Combined calcium antagonism and beta-blockade may modify favourably surges in blood pressure and heart rate in ambulant hypertensives.
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PMID:Effects of calcium antagonism and beta-blockade on haemodynamic responses to stress. 332 Jul 86

We compared verapamil and propranolol hydrochloride for monotherapy of hypertension. Verapamil lowered blood pressure (BP) more effectively than propranolol in black and white patients. Verapamil was equally effective in blacks and whites, whereas propranolol was more effective in whites. Heart rate was reduced by 6.0 beats per minute by verapamil, and by 13.6 beats per minute by propranolol. In blacks, verapamil lowered systolic BP 16.9 vs 8.1 mm Hg for propranolol; verapamil reduced diastolic BP 12.8 vs 8.6 mm Hg for propranolol. In whites, verapamil lowered systolic BP 19.0 vs 12.7 mm Hg for propranolol; verapamil reduced diastolic BP 16.7 vs 12.3 mm Hg for propranolol. Increases in systolic BP were observed in 22% and 3.4% of patients receiving propranolol and verapamil, respectively. The PR interval was increased from 163.5 to 174.9 ms for verapamil vs 160.3 to 164.4 ms for propranolol. Constipation (15%) and headaches (10%) were most frequent complaints for verapamil vs fatigue (18%) and dizziness (7%) for propranolol. Changes in blood biochemistry values were of small magnitude. We conclude that verapamil monotherapy is a safe and effective means of achieving BP control in patients with essential hypertension.
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PMID:A comparison of verapamil and propranolol for the initial treatment of hypertension. Racial differences in response. 353 60


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