Diuretics is a medicines that increase the allocation of kidneys of sodium ions and water and causing therefore decrease the amount of fluid in the body. Diuretics are divided on loop diuretics, Potassium-sparing diuretics, and osmotic. Loop diuretics increase the allocation from the body of sodium ions and to a lesser extent potassium ions. They include furosemide and close to it in the structure of bumetanide, ethacrynic acid (phenoxyacetic acid derivative): dichlothiazidum and close to them on the Effects of oxodolin and clopamid; aminophylline (a derivative of xanthine). Potassium-sparing diuretics, characterized in that simultaneously with the increased excretion of sodium ions from the body delayed excretion of potassium ions include aldosterone antagonist spironolactone, and triamterene (a derivative aminopteridina) and amiloride (a derivative of pyrazinamide). Osmotic diuretics are mannitol and urea. The main effect of diuretics is their natriuretic effect, ie ability to increase the allocation of sodium ions from the body due to the reduction of reabsorption in the tubules of the kidneys.