How do NSAIDs influence blood pressure control and the effectiveness of antihypertensive therapy?

How do NSAIDs influence blood pressure control and the effectiveness of antihypertensive therapy?

• A. Increase renal prostaglandin synthesis leading to natriuresis and BP lowering.
• B. Directly block angiotensin converting enzyme.
• C. Reduce renal prostaglandin synthesis leading to Na+ and water retention and BP elevation.
• D. Enhance vascular smooth muscle relaxation independent of renal effects.

Answer: (C)

NSAIDs inhibit cyclooxygenase, lowering renal prostaglandin synthesis. In the kidney prostaglandins normally promote dilation of the afferent arteriole and support natriuresis. When their production is reduced, renal perfusion and GFR can fall, sodium and water retention increase, and blood pressure can rise. This also blunts the effectiveness of antihypertensive medicines, especially diuretics and other drugs whose renal effects depend on maintaining natriuresis and proper renal blood flow. So the best description is that NSAIDs reduce renal prostaglandin synthesis leading to Na+ and water retention and BP elevation. Why the other ideas don’t fit: increasing prostaglandin synthesis would promote natriuresis and lower BP (opposite of what NSAIDs do); directly blocking ACE is not an action of NSAIDs; and while NSAIDs can affect vascular tone, their BP-raising effect is primarily through renal mechanisms rather than a straightforward, independent vascular smooth muscle relaxation.

NSAIDs inhibit cyclooxygenase, lowering renal prostaglandin synthesis. In the kidney prostaglandins normally promote dilation of the afferent arteriole and support natriuresis. When their production is reduced, renal perfusion and GFR can fall, sodium and water retention increase, and blood pressure can rise. This also blunts the effectiveness of antihypertensive medicines, especially diuretics and other drugs whose renal effects depend on maintaining natriuresis and proper renal blood flow.

So the best description is that NSAIDs reduce renal prostaglandin synthesis leading to Na+ and water retention and BP elevation.

Why the other ideas don’t fit: increasing prostaglandin synthesis would promote natriuresis and lower BP (opposite of what NSAIDs do); directly blocking ACE is not an action of NSAIDs; and while NSAIDs can affect vascular tone, their BP-raising effect is primarily through renal mechanisms rather than a straightforward, independent vascular smooth muscle relaxation.