High ceiling diuretics

INHIBITORS OF NA+-K+-2CL- SYMPORT (LOOP DIURETICS, HIGH-CEILING DIURETICS)... 

Inhibitors of Na+-K+-2C1 Symport (Loop Diuretics, High-Ceiling Diuretics)... 

Diuretics are needed to return to normal the expanded extracellular volume that other antihypertensive agents produce, such as fluid retention and blood volume expansion, via compensatory mechanisms of the body. The loss of efficacy of antihypertensive agents can be restored if a diuretic is used concomitandy. In the treatment of hypertension, high ceiling or loop diuretics, such as furosemide, ethacrynic acid, and bumetanide, are no more efficacious than the thiazide-type of diuretics. In fact, these agents cause more side effects, such as dehydration, metaboHc alkalosis, etc, and therefore, should not be used except in situations where rapid elimination of duid volume is cleady indicated. 

Potassium Sparing Diuretics. Triamterene and amiloride, potassium sparing diuretics, by themselves produce only slight antihypertensive effects. The main use is to prevent or to treat the hypokalemia induced by thiazide-type and high ceiling loop diuretics, such as furosemide and bumetanide. 

Ascites. Patients with cirrhosis, especially fiver cirrhosis, very often develop ascites, ie, accumulation of fluid in the peritoneal cavity. This is the final event resulting from the hemodynamic disturbances in the systemic and splanchnic circulations that lead to sodium and water retention. When therapy with a low sodium diet fails, the dmg of choice for the treatment of ascites is furosemide, a high ceiling (loop) diuretic, or spironolactone, an aldosterone receptor antagonist/potassium-sparing diuretic. 

High ceiling diuretics, 5 169 High chrome-nickel stainless steels, pickling, 16 223... 

Loop diuretics include furosemide (frusemide), piretanide, and bumeta-nide. With oral administration, a strong diuresis occurs within 1 h but persists for only about 4 h. The effect is rapid, intense, and brief (high-ceiling diuresis). 

Frequent serum electrolyte analysis is essential during therapy with the high-ceiling diuretics. Overdose may result in a rapid reduction of blood volume, dizziness, headache, orthostatic hypotension, hyponatremia, and hypokalemia. Nausea, vomiting, diarrhea, and loss of appetite are especially common with ethacrynic acid. 

The high-ceiling diuretics act primarily by inhibiting electrolyte reabsorption in the thick ascending limb of the loop of Henle. As much as 20% of the filtered Na may be reabsorbed in the loop of Henle. 

Edema The high ceiling diuretics are effective for the treatment of edema of cardiac, hepatic or renal origin. They are the drug of choice in case of congestive heart failure. These are preferred initially in all cases for rapid mobilization of edema fluid. 

In the management of refractory edema, the high ceiling diuretics may be used in conjunction with other types of diuretics. They are also useful for forced diuresis in hypnotic or other poisonings. 

Furosemide has a general effect of the reabsorption of sodium and chloride throughout the tubule system especially in the loop of Henle and is also a high-ceiling diuretic because of its potent, prompt onset of action (5 minutes after i.v. administration, within 1 hour when taken orally). Its mode of action is to inhibit the Na /K /2 Cl" transport mechanism. This drug has been involved in... 

High-ceiling diuretics, sulfonamide (furosemide, bumetanide, torasemide, piretanide)... 

Schafer JA, Troutman SL, Andreoli TE (1974) Volume reabsorption, transepithelial potential differences, and ionic permeability properties in mammalian superficial proximal straight tubules. J Gen Physiol 64 582-607 Schlatter E, Greger R, Weidtke C (1983) Effect of high ceiling diuretics on active salt transport in the cortical thick ascending limb of Henle s loop of rabbit kidney. Correlation of chemical structure and inhibitory potency. Pfltigers Arch 396 210-217... 

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