Interrelationship between the renin-angiotensin system and bradykinin.
thickness of the left ventricle in both normal and hy-pertrophied myocardium. ACE inhibitors lack metabolic side effects and do not alter serum lipids.
The onset of action following oral administration of captopril is about 15 minutes, with peak blood levels achieved in 30 to 60 minutes. Its apparent biological half-life is approximately 2 hours, with its antihypertensive effects observed for 6 to 10 hours. The kidneys appear to play a major role in the inactivation of captopril.
Captopril, as well as other ACE inhibitors, is indicated in the treatment of hypertension, congestive heart failure, left ventricular dysfunction after a myocardial infarction, and diabetic nephropathy. In the treatment of essential hypertension, captopril is considered first-choice therapy, either alone or in combination with a thiazide diuretic. Decreases in blood pressure are primarily attributed to decreased total peripheral resistance or afterload. An advantage of combining captopril therapy with a conventional thiazide diuretic is that the thiazide-induced hypokalemia is minimized in the presence of ACE inhibition, since there is a marked decrease in angiotensin II-induced aldosterone release.
If the patient is asymptomatic, captopril can be used as monotherapy in the treatment of congestive heart failure. The use of ACE inhibitors in the treatment of congestive heart failure is supported by results from large-scale clinical trials demonstrating a general reduction in the relative risk of death. In symptomatic patients captopril should be used in conjunction with a diuretic because of the weak natriuretic properties of ACE inhibitors. In combination, captopril will reduce afterload and preload and prevent diuretic-induced activation of the renin-angiotensin system. Finally, ACE inhibitors may slow the progression of congestive heart failure by limiting left ventricular hypertrophy.
In the treatment of diabetic nephropathy associated with type I insulin-dependent diabetes mellitus, capto-pril decreases the rate of progression of renal insufficiency and retards the worsening of renal function.
Approximately 10% of the patients treated with captopril report a dose-related maculopapular rash that often disappears when the dosage of captopril is reduced. Other common adverse effects are fever, a persistent dry cough (incidence as high as 39%), initial dose hypotension, and a loss of taste that may result in anorexia. These effects are reversed when drug therapy is discontinued. More serious toxicities include a 1% incidence of proteinuria and glomerulonephritis; less common are leukopenia and agranulocytosis. Since food reduces the bioavailability of captopril by 30 to 40%, administration of the drug an hour before meals is recommended. All converting enzyme inhibitors are contraindicated in patients with bilateral renal artery disease or with unilateral renal artery disease and one kidney. Use under these circumstances may result in renal failure or paradoxical malignant hypertension.
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All you need is a proper diet of fresh fruits and vegetables and get plenty of exercise and you'll be fine. Ever heard those words from your doctor? If that's all heshe recommends then you're missing out an important ingredient for health that he's not telling you. Fact is that you can adhere to the strictest diet, watch everything you eat and get the exercise of amarathon runner and still come down with diabetic complications. Diet, exercise and standard drug treatments simply aren't enough to help keep your diabetes under control.