ACE inhibitors

Question 1

Mechanism of action ?

Answer 1

ACE converts angiotensin I to angiotensin II. The latter is a potent vasoconstrictor that promote the secretion of Aldosterone. Inhibiting the ACE helps reduce peripheral vascular resistance (afterload). It particularly dilates the efferent arteriole which decreases the intra-glomerular pressure &slows down the progression of chronic kidney diseases. Reducing the Aldosterone levels increases water &Na exretion which reduces the venous return (preload).

Question 2

Indications ?

Answer 2

• first or second line treatment in hypertension,
• first-line treatment in all grades of chronic heart failure,
• reduces the risk of cardiovascular complications (idm) in ischemic heart diseases,
• diabetic nephropathy and CKD with proteinuria to reduce proteinuria &the progression of nephropathy.

Question 3

Important AE ?

Answer 3

Three major &common AE that can cause or worse renal failure; particularly in patients with renal stenosis that rely on constriction of the efferent arteriole to maintain intra-glomeruluar filtration.: hypotension, persistent dry cough (due to bradykinin that are inactivated by ACE) and hyperkalemia. Rare but important indiosyncratic AE are angioedema &anaphylactoid reactions.

Question 4

Important cautions ?

Answer 4

ACE inhibitors should be avoided in patients with renal stenosis or acute kidney injuries, in women who are, or could become pregnant, &those lactating.
Although ACE inhibitors may be useful in some forms of CKD, lower doses &kidney function monitoring are a necessity.

Question 5

Important interactions ?

Answer 5

with other hyperkalemic drugs; K supplements or anti-aldosterons.
NSAIDs increase the risk of renal failure when used while on ACE inhibitors.

Question 6

Name some of the ACE inhibitors ?

Answer 6

RAMIPRIL;
PERINDOPRIL;
LISINOPRIL.

Question 7

How are ACE inhibitors taken ?

Answer 7

orally, once daily, with or without food, best to take first dose before bed to reduce symptomatic hypotension.
starting dose is usually at 1,25 mg for heart failure, 2,5 mg for other indications (ramipril). It is titrated up for a maximum of 10 mg a day within the span of weeks according the patient’s response.

Question 8

Define angioedema ?

Answer 8

Angioedema is an area of swelling of the lower layer of skin and tissue just under the skin or mucous membranes. The swelling may occur in the face, tongue, larynx, abdomen, or arms and legs.