Clinical Evaluation of Chlorothiazide

[摘要] Chlorothiazide, commercially known as Diuril®, has been demonstrated to be an effective oral diuretic agent since its introduction to clinical practice 2 years ago. The chemical structure of the compound is similar to acetazolamide and sulfanilamide. The ability of chlorothiazide, by virtue of its attached sulfamyl group, to inhibit carbonic anhydrase plays only a small role in the drug's long-term action. The mechanism of the diuretic capacity of chlorothiazide is not known, though it is postulated that the drug interferes with sodium and chloride reabsorption in the proximal convoluted tubule of the kidney. Potassium may be exchanged for some of the sodium in the distal portion of the nephron.The diuretic action of chlorothiazide has proved particularly valuable in the management of edematous patients with congestive heart failure, and may be of benefit in the nephrotic syndrome, cirrhosis of the liver or fluid retention following steroid therapy. Since the drug acts chiefly on the kidneys and may depress glomerular filtration and renal plasma flow, its usefulness is limited if kidney function is poor. The average daily dose of chlorothiazide ranges from 0.5 to 1 gram; tolerance to the drug is uncommon and may be given over a period of many months. In patients with initially low potassium levels or those who excrete large amounts of this ion, supplemental oral salts of potassium should be prescribed. The side effects of chlorothiazide involving electrolyte imbalance are usually transient; rare and unusual toxic effects (skin rashes, paresthesias, etc.) are reported.Chlorothiazide has the ability to reduce blood pressure, probably secondary to mild salt depletion. It has been a useful adjuvant to Rauwolfia preparations and ganglionic blocking agents in achieving desired hypotensive effects.

[学科分类] 儿科学