Which of the following statements regarding ACE inhibitors is true?
High-Yield Explanation
Ans. (B) Omission of prior diuretic dose decreases the risk of postural hypotension(Ref: KDT 8th/e p531)Angiotensin Converting Enzyme Inhibitors (ACEI)*This group of drugs inhibits the enzyme kininase II or ACE. So, these drugs decrease the activity of RAAS and also potentiate the vasodilatory action of bradykinin. Because these are preventing the conversion of angiotensin I to angiotensin II, so these can decrease the action of the former but not the latter.*ACEI are used for the treatment of hypertension, CHF, evolving MI, diabetic nephropathy, diabetic retinopathy, non-diabetic renal disease and also in scleroderma crisis. These drugs reduce proteinuria in diabetic as well as non-diabetic renal disease and also prevent the manifestations of scleroderma crisis which are mediated by angiotensin II.*This group of drugs is more effective in sodium depleted states (like diuretic use) because activity of RAAS is more in such cases (to compensate for salt loss). These drugs may cause postural hypotension in diuretic treated patients, which otherwise is a relatively rare adverse effect.*Lisinopril is longer acting than enalapril. Former can be given once daily whereas latter is required twice a day.