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agents that increase the excretion of urine and decrease the amount of fluid in the tissues and serous cavities. Natriuretics increase the excretion of sodium ions. Diuretics are used primarily to treat edema accompanying cardiovascular, liver, and kidney diseases. Depending on their effect, they are classified as renal diuretics, which act directly on the kidneys and have the most pronounced effect, and extrarenal diuretics, which act indirectly through other systems in the body.

Renal diuretics act by blocking the kidney enzymes responsible for the transport of electrolytes, as well as by inhibiting reabsorption in the terminal tubules, which intensifies the excretion of sodium, chlorine, and potassium ions. Among the renal diuretics are the mercury compounds Mercusal and Novurit and carbonic anhydrase inhibitors such as Diacarb and dichlorphenamide (Daranid)—sulfonamide derivatives that intensify the excretion of bicarbonate, causing a drop in the alkaline reserve in the blood and, in some cases, acidosis. Benzothiadizine and sulfamoylanthranilic and dichlorophenoxyacetic acid derivatives such as dichlothiazide (Hypothiazide), furosemide (Lasix), and ethacrynic acid (Uregit) are extremely potent diuretics that sharply increase the excretion of sodium and have a hypotensive effect. Pyrimidine and pteridine derivatives, such as Allacyl and triamterene (pterofen), inhibit tubular reabsorption of sodium and chlorine ions but do not affect the excretion of potassium. Aldosterone antagonists, including spironolactone (Aldactone and Verospiron), increase the excretion of sodium and decrease the excretion of potassium and urea.

Depending on how they act, extrarenal diuretics are classified as osmotic and other types of agents. Among the osmotic agents are potassium acetate, mannitol, and urea, which are excreted by the kidneys and absorb water. They cause the excretion of sodium and chlorine in proportion to the increase in volume of urine and are used to lower intracranial pressure and reduce cerebral edema. Acid-forming diuretics include ammonium chloride and potassium chloride, which act by the transformation of cations. The ammonium ion is transformed into urea in the liver, the calcium ion settles in the intestine in the form of phosphate or carbonate, and chlorine ions occur in excess in the blood plasma and are excreted by the kidneys with sodium.

Extracts and tinctures are sometimes prepared for use as diuretics from bearberry leaf (tincture or decoction), field horsetail (decoction or fluid extract), and Orthosiphon leaf (tincture).

References in periodicals archive ?
Loop diuretics, thiazide diuretics, beta-blockers, ARBs, and alpha-blockers were not associated with the risk of NOF development in elderly hypertensive patients.
All these guidelines recommend use of thiazide diuretics as the drug of first choice in patients of Stage 1 hypertension without any compelling indications.
The third subclass of diuretics, thiazide diuretics are prescribed to patients with mild or moderate HTN (Vallerand, Sanoski, & Deglin, 2013).
JNC 8 recommends thiazide diuretics and CCBs as first-line therapy--a recommendation that is evidence-based.
More than two-thirds of older adults have high blood pressure in the United States and thiazide diuretics are often recommended as the initial medication for these hypertensive patients.
If a calcium channel blocker is not tolerated as second line, consider using thiazide diuretics.
In a study of predominantly black hypertensive patients conducted more than a decade ago in a predominantly urban population, Seedat (14) found that black patients responded best to diuretics, vasodilators or CCBs; their response to BB and ACEIs was poor, unless these agents were combined with thiazide diuretics.
The null hypothesis of the parent study is that financial incentives would not significantly increase the number of patients who discussed thiazide diuretics with their primary care providers--and the null hypothesis was not disproved.
Thiazide diuretics act on the renal tubules to inhibit reabsorption of sodium and water.
Thiazide diuretics are often recommended as the first medication to use to control blood pressure, but I've heard that a large study called ALLHAT found an association between thiazide diuretics and diabetes.
Hypertension is prevalent in gout patients and they are often treated with anti-hypertensive agents such as thiazide diuretics.