<prompt> DOC for lithium induced Nephrogenic Diabetes InsipidusSpiranolactoneFurosemideAmilorideNone of the above  <response>: AMILORIDE Mechanism of action:- The luminal membrane of late DT and CD cells expresses a distinct renal epithelial or amiloride sensitive Na channel through which Na enters the cell down its electrochemical gradient which is generated by NaK ATPase operating at the basolateral membrane. This Na entry paially depolarizes the luminal membrane creating a -15 mV transepithelial potential difference which promotes secretion of K into the lumen through K channels. Though there is no direct coupling between Na and K channels, more the delivery of Na to the distal nephron--greater is its entry through the Na channel--luminal membrane is depolarized to a greater extent--driving force for K secretion is augmented. As such, all diuretics acting proximally loop diuretics, thiazides, CAse inhibitors promote K secretion. Amiloride and triamterene block the luminal Na channels and indirectly inhibit K excretion Pottasium sparing diuretic. side effects:- Nausea, diarrhoea and headache. Uses:- Amiloride blocks entry of Li through Na channels in the CD cells and mitigates diabetes insipidus induced by lithium. Given as an aerosol it affords symptomatic improvement in cystic fibrosis by increasing fluidity of respiratory secretions. Ref:- kd tripathi; pg num:-589,590 