Therapeutic use: Thiazide diuretics噻嗪类利尿剂，such as hydrochlorothiazide氢氯 噻嗪，act on distal convoluted tubule and inhibit Nat-Cl-symport..Can counteract the Na+and H2O retention effect of direct vasodilators such as hydralazine and therefore are beneficial for combined use Particularly useful for elderly patients,but not effective when kidney function is inadequate. Thiazides reduce blood K+and Mg2+levels,and induce hypokalemia. It also retains Ca2+and decreases urine Ca2+content.It is necessary to monitor serum K+level in patients with cardiac arrhythmias and when digitalis is in use. Loop diuretics亨利氏环类利尿剂，including furosemidei速尿， torsemide:托拉赛米，and ethacrynic acid:利尿酸，are more powerful than thiazides.They are often used for treatment of severe hypertension when direct vasodilators are administered and Na+and H2O retention becomes a problem.Can be used in patients not responding to thiazides.Increase urine Ca2+content. K-sparing diuretics include triamterene氨苯蝶呤，amiloride阿米洛利 (both are Na+channel inhibitors),and spironolactone安体舒通 (aldosterone antagonist).Used for treating hypertension in patients who also take digitalis.This class of drugs enhance the natriuretic effects of other diuretics(e.g.,thiazides)and counteract the K+ depleting effect of these diuretics.5 Therapeutic use: Thiazide diuretics 噻嗪类利尿剂, such as hydrochlorothiazide 氢氯 噻嗪, act on distal convoluted tubule and inhibit Na+-Cl- symport. Can counteract the Na+ and H2O retention effect of direct vasodilators such as hydralazine and therefore are beneficial for combined use. Particularly useful for elderly patients, but not effective when kidney function is inadequate. Thiazides reduce blood K+ and Mg2+ levels, and induce hypokalemia. It also retains Ca2+ and decreases urine Ca2+ content. It is necessary to monitor serum K+ level in patients with cardiac arrhythmias and when digitalis is in use. Loop diuretics 亨利氏环类利尿剂, including furosemide速尿, torsemide托拉赛米, and ethacrynic acid利尿酸, are more powerful than thiazides. They are often used for treatment of severe hypertension when direct vasodilators are administered and Na+ and H2O retention becomes a problem. Can be used in patients not responding to thiazides. Increase urine Ca2+ content. K-sparing diuretics include triamterene氨苯蝶呤, amiloride阿米洛利 (both are Na+ channel inhibitors), and spironolactone安体舒通 (aldosterone antagonist). Used for treating hypertension in patients who also take digitalis. This class of drugs enhance the natriuretic effects of other diuretics (e.g., thiazides) and counteract the K+ depleting effect of these diuretics