Two nurses are discussing the theories of drug-receptor interaction. Which statements are true regarding the affinity of a drug and for its receptor? (Select all that apply)

Choice A reason: ACE inhibitors cause dry cough by inhibiting bradykinin breakdown, which accumulates and irritates the airways. ARBs block angiotensin II receptors without affecting bradykinin, eliminating this side effect. This makes ARBs a suitable alternative for patients experiencing cough, confirming this as the correct choice.

Choice B reason: Hyperkalemia occurs with both ACE inhibitors and ARBs due to reduced aldosterone production, which decreases potassium excretion. Both drug classes affect the renin-angiotensin-aldosterone system similarly, so switching to an ARB does not eliminate this risk, making this choice incorrect for the question.

Choice C reason: Hypotension is a shared side effect of ACE inhibitors and ARBs, as both reduce blood pressure by inhibiting the renin-angiotensin system. ARBs block angiotensin II receptors, causing vasodilation similar to ACE inhibitors, so this side effect persists, making this choice incorrect.

Choice D reason: Angioedema, though rare, can occur with both ACE inhibitors and ARBs. While less common with ARBs, it’s not eliminated, as it may result from mechanisms beyond bradykinin accumulation. Switching to an ARB doesn’t guarantee avoidance of angioedema, making this choice incorrect.

Choice A reason: Adrenergic neuron blockers, like guanethidine, reduce blood pressure by inhibiting norepinephrine release. They are not first-line for stage 1 hypertension (140-159/90-99 mm Hg). Their side effects, like orthostatic hypotension, make them less suitable. Lifestyle changes are preferred initially for this patient’s mild elevation and normal diagnostic tests, making this choice inappropriate.

Choice B reason: Beta blockers, like atenolol, reduce heart rate and cardiac output, lowering blood pressure. They are not first-line for stage 1 hypertension without compelling indications (e.g., heart failure). Guidelines recommend lifestyle modifications first for this patient’s blood pressure range, as they effectively reduce risk without medication side effects, making this choice less suitable.

Choice C reason: For stage 1 hypertension (140-159/90-99 mm Hg) with normal diagnostic tests, guidelines recommend lifestyle changes, such as diet, exercise, and weight loss, as first-line treatment. These reduce blood pressure by improving vascular health and reducing cardiac strain, offering a low-risk approach to manage mild hypertension effectively, making this the correct choice.

Choice D reason: ACE inhibitors, like lisinopril, block angiotensin II formation, reducing blood pressure. They are effective but not first-line for stage 1 hypertension without comorbidities. Lifestyle changes are prioritized to avoid medication side effects like cough or hyperkalemia, making this choice less appropriate for initial management in this patient.