Correct Answer: B

Rationale: Nalidixic acid can intensify the effects of oral anticoagulants by displacing these agents from binding sites on plasma proteins. When an oral anticoagulant, like warfarin sodium (Coumadin), is combined with nalidixic acid, a decrease in the anticoagulant dosage may be necessary to avoid excessive anticoagulation and potential bleeding risks.

Correct Answer: C

Rationale: A respiratory rate of 10 breaths per minute indicates respiratory depression, a severe side effect of meperidine (Demerol) that necessitates immediate intervention to prevent further complications. Constipation, drowsiness, and nausea are common but less urgent side effects that do not pose an immediate life-threatening risk.

Correct Answer: B

Rationale: Bethanechol chloride (Urecholine) should not be administered to clients with urinary strictures as it can contract the bladder and increase pressure within the urinary tract. In individuals with urinary strictures, this elevated pressure may lead to bladder rupture. Therefore, caution is advised when considering the use of Bethanechol chloride in clients with urinary strictures to prevent potential complications.

Correct Answer: C

Rationale: The correct answer is C. Hydrochlorothiazide is a thiazide diuretic, which can lead to hypokalemia, hyperglycemia, hypercalcemia, hyperlipidemia, and hyperuricemia. It is a sulfa-based medication, so individuals with a sulfa allergy are at risk for an allergic reaction when taking hydrochlorothiazide.

Correct Answer: B

Rationale: Spinach is high in vitamin K, which antagonizes the effects of warfarin sodium, an anticoagulant medication. Therefore, clients taking warfarin should avoid consuming foods rich in vitamin K, like spinach, to maintain the medication's effectiveness.