A 50-year-old man has a history of frequent episodes of renal colic with high calcium renal stones. The most useful diuretic in the treatment of recurrent calcium stones is

THIAZIDE AND RELATED DIURETICS (Inhibitors of Na+ Cl- sympo) mech of action:- The primary site of action is the coical diluting segment or the early DT. Here they inhibit Na+-Cl- sympo at the luminal membrane. Uses:- 1. Edema:- Thiazidesmay be used for mild-to- moderate cases. They act best in cardiac edema; are less effective in hepatic or renal edema. Thiazides are powerless in the presence of renal failure, but metolazone may still act. Cirrhotics often develop refractoriness to thiazides due to development of secondary hyperaldosteronism. 2. Hypeension:- Thiazides and related diure tics, especially chlohalidone are one of the first line drugs. 3. Diabetes insipidus:- Thiazides decrease positive free water clearance and are the only drugs effective in nephrogenic diabetes insipidus. 4. Hypercalciuria:- with recurrent calcium stones in the kidney. Thiazides act by reducing Ca2+ excretion. Ref:- kd tripathi; pg num:-582,584