The kidneys comprise only of body weight, yet they receive 25% of the cardiac output. Drugs that affect renal function have important roles in cardiac failure and hypertension. Disease of the kidney must be taken into account when prescribing drugs that are eliminated by it. Diuretic drugs: their sites and modes of action, classification, adverse effects and uses in cardiac, hepatic, renal and other conditions. Carbonic anhydrase inhibitors. Cation-exchange resins and their uses. Alteration of urine pH Drugs and the kidney. Adverse effects. Drug-induced renal disease: by direct and indirect biochemical effects and by immunological effects. Prescribing. | SECTION 5 Kidney and genitourinary tract SYNOPSIS The kidneys comprise only of body weight yet they receive 25 of the cardiac output. Drugs that affect renal function have important roles in cardiac failure and hypertension. Disease of the kidney must be taken into account when prescribing drugs that are eliminated by it. Diuretic drugs their sites and modes of action classification adverse effects and uses in cardiac hepatic renal and other conditions Carbonic anhydrase inhibitors Cation-exchange resins and their uses Alteration of urine pH Drugs and the kidney Adverse effects Drug-induced renal disease by direct and indirect biochemical effects and by immunological effects Prescribing for renal disease adjusting the dose according to the characteristics of the drug and to the degree of renal impairment Nephrolithiasis and its management Pharmacological aspects of micturition Benign prostatic hyperplasia Erectile dysfunction See also Ch. 23 Definition. A diuretic is any substance which increases urine and solute excretion. This wide definition however includes substances not commonly thought of as diuretics . water. To be therapeutically useful a diuretic should increase the output of sodium as well as of water since diuretics are normally required to remove oedema fluid composed of water and solutes of which sodium is the most important. Diuretics are among the most commonly-used drugs perhaps because the evolutionary advantages of sodium retention have left an aging population without salt-losing mechanisms of matching efficiency. Each day the body produces 1801 of glomerular filtrate which is modified in its passage down the renal tubules to appear as of urine. Thus a 1 reduction in reabsorption of tubular fluid will more than double urine output. Clearly drugs that act on the tubule have considerable scope to alter body fluid and electrolyte balance. Most clinically useful diuretics are organic anions which are transported directly from the blood .
