Hygroton

Chlortalidone, also known as chlorthalidone, is a diuretic medication used to treat high blood pressure, swelling including that due to heart failure, liver failure, and nephrotic syndrome, diabetes insipidus, and renal tubular acidosis. In high blood pressure it is a preferred initial treatment; in resistant high blood pressure chlortalidone is preferred over hydrochlorothiazide. It is also used to prevent calcium-based kidney stones. It is taken by mouth. Effects generally begin within three hours and last for up to 3 days. Chlortalidone, also known as chlorthalidone, is a diuretic medication used to treat high blood pressure, swelling including that due to heart failure, liver failure, and nephrotic syndrome, diabetes insipidus, and renal tubular acidosis. In high blood pressure it is a preferred initial treatment; in resistant high blood pressure chlortalidone is preferred over hydrochlorothiazide. It is also used to prevent calcium-based kidney stones. It is taken by mouth. Effects generally begin within three hours and last for up to 3 days. Common side effects include low blood potassium, high blood sugar, dizziness, and erectile dysfunction. Other serious side effects may include gout, allergic reactions, and low blood pressure. Chlortalidone has a higher risk of side effects than hydrochlorothiazide. While it may be used in pregnancy it is a less preferred option. Specifically it is a thiazide-like diuretic. How it works is not completely clear but is believed to involve increasing the amount of sodium and water lost by the kidneys. Chlortalidone was patented in 1957 and came into medical use in 1960. It is available as a generic medication. In the United States the wholesale cost is about US$13.50 a month. In 2016 it was the 174th most prescribed medication in the United States with more than 3 million prescriptions. Chlortalidone is considered a first-line medication for treatment high blood pressure, and is preferred over hydrochlorothiazide because of its greater efficacy and because of the greater body of evidence supporting its use. A meta-analysis of trials of chlortalidone for high blood pressure found that lower doses of chlortalidone (e.g., 12.5 mg daily in ALLHAT study) had maximal blood pressure lowering effect and that higher doses did not lower it more. Chlortalidone has a modestly greater effect on blood pressure than hydrochlorothiazide but the two medications have similar effects on lowering potassium. The thiazide-like diuretics (chlortalidone and indapamide) are more effective than the thiazide-type diuretics (including hydrochlorothiazide) for reducing the risk of heart attack, stroke, and heart failure in persons with high blood pressure and the thiazide-like and thiazide-type diuretics have similar rates of adverse effects. Chlortalidone is more effective than hydrochlorothiazide for prevention of heart failure in persons with high blood pressure. Chlortalidone may improve edema (swelling) by increasing urinary salt and water excretion, lowering intravascular hydrostatic pressure and thereby lowering transcapillary pressure. See Starling Equation. Edema may be caused by either increased hydrostatic pressure or reduced oncotic pressure in the blood vessels. Edema due to increased hydrostatic pressure may be a result of serious cardiopulmonary disease (which reduces glomerular perfusion in the kidney) or to kidney injury or disease (which may reduce glomerular excretion of salt and water by the kidney) or due to relatively benign conditions such as menstrual-related fluid retention, or as an adverse effect of dihydropyridine calcium channel blockers, which commonly cause swelling of the feet and lower legs. Edema due to decreased oncotic pressure may be a result of leaking of blood proteins through the glomeruli of an injured kidney or a result of decreased synthesis of blood proteins by the liver. Regardless of cause, chlortalidone may sometimes improve the severity of edema by reducing intravascular volume and thereby reducing intravascular hydrostatic pressure. Chlortalidone is used to treat left ventricular hypertrophy in the heart; it works chiefly by lowering blood pressure, and thereby reducing systemic vascular resistance. There is evidence that chlortalidone is superior to hydrochlorothiazide for reducing the mass of the left ventricle of the heart in persons with enlargement of the left ventricle of the heart. Chlortalidone is superior to angiotensin converting enzyme Inhibitors or angiotensin II receptor blockers for inducing regression of enlargement of the left ventricle, which is the main pumping chamber of the heart. Chlortalidone decreases mineral bone loss by promoting calcium retention by the kidney, and by directly stimulating osteoblast differentiation and bone mineral formation. A Cochrane review found tentative evidence that thiazide exposure was associated with a reduced risk of hip fracture. A secondary analysis of data from the ALLHAT study found that chlortalidone reduced risk of hip and pelvis fracture.