A patient prescribed a muscarinic-receptor blocker will require assessment for what side effect?
Explanation & Rationale
Choice A reason: Muscarinic receptor blockers inhibit parasympathetic activity, reducing salivary gland secretion via acetylcholine pathways. This causes dry mouth, as muscarinic receptors in salivary glands are blocked, decreasing saliva production. This anticholinergic effect is common in drugs like benztropine, requiring assessment to manage discomfort and prevent oral health issues. Choice B reason: Orthostatic hypotension is linked to alpha-1 adrenergic blockade, not muscarinic receptors. Muscarinic blockers affect cholinergic pathways, not vascular tone regulated by norepinephrine. While autonomic effects occur, hypotension is not a primary consequence, making this side effect unrelated to muscarinic receptor antagonism. Choice C reason: Pseudoparkinsonism results from dopamine receptor blockade, common in antipsychotics, not muscarinic blockers. Muscarinic receptors regulate parasympathetic functions like salivation, not motor control. Blocking muscarinic receptors may alleviate parkinsonism by balancing cholinergic-dopaminergic activity, making this an incorrect side effect for assessment. Choice D reason: Gynecomastia is associated with hormonal imbalances or dopamine blockade, not muscarinic receptors. Muscarinic blockers affect cholinergic systems, not prolactin or estrogen pathways. This side effect is unrelated to muscarinic antagonism, which primarily causes anticholinergic effects like dry mouth, not endocrine changes.