Following is true about frusemide

Ans is 'c' i.e. It is used in pulmonary edema Loop diuretics are used in all types of edema because of their diuretic effect But when frusemide is given i.v. in acute pulmonary edema it acts by vasodilator action that preceedes diuretic action.Intravenous furosemide causes prompt increase in systemic venous capacitance and decreases left ventricular filling pressure even before the diuretic response is apparent. This is responsible for the quick relief it affords in the left ventricular failure and pulmonary edema.Frusemide acts on the thick portion of the ascending limb of the loop of Henle where Frusemide inhibits Na+, K+-2Cl- cotransport.It is a orally and rapidly acting highly efficacious diuretic.Its maximal natriuretic effect is much greater than that of other classes of diuretics.The diuretic response goes on increasing with increasing dose i.e. they have a high "ceiling" of effect. Indeed they are so efficacious that overtreatment can dehydrate the patient.It is given i.v. only in case of acute pulmonary edema.