To control asthma, a client in a residential treatment facility uses a fluticasone propionate and salmeterol discus inhalation system, which provides an inhaled powdered form of these combined medications. Which instruction should the nurse provide to this client’s caregivers?

Captopril is an angiotensin converting enzyme inhibitor that works by vasodilation.

Choice A: Angiotensin Converting Enzyme Inhibitor

Reason:

Captopril is classified as an angiotensin converting enzyme (ACE) inhibitor. ACE inhibitors work by blocking the conversion of angiotensin I to angiotensin II, a potent vasoconstrictor. By inhibiting this conversion, ACE inhibitors reduce the levels of angiotensin II, leading to vasodilation, decreased blood pressure, and reduced workload on the heart. This mechanism is particularly beneficial in managing hypertension and heart failure. Additionally, ACE inhibitors like captopril help in reducing the progression of diabetic nephropathy by decreasing glomerular pressure.

Choice B: Aldosterone Agonist

Reason:

Aldosterone agonists are drugs that mimic the action of aldosterone, a hormone that increases sodium and water reabsorption in the kidneys, leading to increased blood volume and blood pressure. This is the opposite of what captopril does. Captopril, as an ACE inhibitor, actually reduces aldosterone secretion, leading to decreased sodium and water retention, which helps lower blood pressure. Therefore, captopril cannot be classified as an aldosterone agonist.

Choice C: Angiotensin II Receptor Blocker

Reason:

Angiotensin II receptor blockers (ARBs) work by blocking the action of angiotensin II at its receptor sites, preventing vasoconstriction and aldosterone secretion. While ARBs and ACE inhibitors both target the renin-angiotensin-aldosterone system (RAAS), they do so at different points. Captopril is an ACE inhibitor, not an ARB. ARBs include drugs like losartan and valsartan, which are used when patients cannot tolerate ACE inhibitors due to side effects like coug.

Choice D: Lowering the Heart Rate

Reason:

Lowering the heart rate is not the primary mechanism of action for captopril. This effect is more commonly associated with beta-blockers, which reduce heart rate and myocardial contractility to lower blood pressure and reduce cardiac workload. Captopril, on the other hand, primarily works through vasodilation by inhibiting the formation of angiotensin II. While it may have some indirect effects on heart rate by reducing blood pressure, this is not its main mechanism.

Choice E: Reducing Inflammation

Reason:

Reducing inflammation is not a primary action of captopril. Anti-inflammatory effects are typically associated with nonsteroidal anti-inflammatory drugs (NSAIDs) or corticosteroids. While there is some evidence that ACE inhibitors may have minor anti-inflammatory effects due to their impact on the RAAS, this is not their primary function. Captopril is mainly used for its vasodilatory effects to manage hypertension and heart failure.

Choice F: Diuresis

Reason:

Diuresis, or increased urine production, is not the primary mechanism of action for captopril. Diuretics, such as furosemide or hydrochlorothiazide, are specifically used to promote diuresis by acting on different parts of the renal tubules to increase the excretion of sodium and water. While captopril can lead to mild diuresis by reducing aldosterone levels, this is not its main therapeutic action.

Choice G: Vasodilation

Reason:

Vasodilation is the correct mechanism of action for captopril. By inhibiting the conversion of angiotensin I to angiotensin II, captopril reduces vasoconstriction and promotes vasodilation. This leads to a decrease in blood pressure and an overall reduction in the workload on the heart. Vasodilation is a key therapeutic effect of ACE inhibitors, making them effective in treating conditions like hypertension and heart failure.

Choice A Reason:

Avoiding taking allopurinol on an empty stomach is a common recommendation to prevent stomach upset. Taking the medication with food can help reduce gastrointestinal discomfort, making this advice appropriate and not requiring additional instruction.

Choice B Reason:

Consuming 2 liters of water daily is advised when taking allopurinol to help prevent kidney stones and ensure proper hydration. Adequate fluid intake helps to dilute the urine and reduce the risk of uric acid crystal formation, making this advice correct and not needing further instruction.

Choice C Reason:

Reducing caffeine and acidic intake can be beneficial for individuals taking allopurinol, as these substances can increase uric acid levels and potentially exacerbate gout symptoms. This advice is appropriate and does not require additional instruction.

Choice D Reason:

Doubling the dose if a dose is missed is incorrect and potentially dangerous. Allopurinol should be taken exactly as prescribed, and doubling up on doses can increase the risk of side effects and toxicity. If a dose is missed, the client should take it as soon as they remember, but if it is almost time for the next dose, they should skip the missed dose and continue with their regular schedule. This instruction requires correction by the nurse.