A patient has allergies and takes an antihistamine. The patient wants to know how the drug works. The nurse understands that antihistamines work because they are what?

Choice A reason: Furosemide, a loop diuretic, promotes potassium excretion, risking hypokalemia. The patient’s potassium level (3.1 mEq/L) is below normal (3.5-5.0 mEq/L), indicating hypokalemia, which can cause arrhythmias. Administering Lasix without addressing this could worsen the electrolyte imbalance, making this choice unsafe and incorrect.

Choice B reason: Oxygen administration addresses respiratory issues, not electrolyte imbalances like hypokalemia (3.1 mEq/L) caused by furosemide. There’s no indication of hypoxia in the lab results or scenario. This action doesn’t correct the potassium deficit or prevent further depletion, making it irrelevant and incorrect.

Choice C reason: Furosemide exacerbates hypokalemia (patient’s potassium: 3.1 mEq/L), risking cardiac arrhythmias or muscle weakness. Holding the dose prevents further potassium loss, and notifying the physician allows for correction (e.g., potassium supplements) and reassessment of therapy, making this the safest and most appropriate action.

Choice D reason: A 24-hour urine collection assesses renal function or output but doesn’t address the immediate concern of hypokalemia (3.1 mEq/L) caused by furosemide. This test is irrelevant to correcting the electrolyte imbalance or preventing further depletion, making it an inappropriate action in this scenario.

Choice A reason: Pseudoephedrine, a decongestant, relieves nasal congestion by vasoconstriction but doesn’t address inflammation or histamine-mediated symptoms like sneezing or itching in rhinitis. It’s less effective than intranasal corticosteroids, which target the underlying allergic response, making this choice less optimal for comprehensive rhinitis treatment.

Choice B reason: Intranasal cromolyn sodium stabilizes mast cells, reducing histamine release, but it’s less effective than corticosteroids for rhinitis. Atrovent (ipratropium) is incorrectly referenced here, as it treats rhinorrhea, not inflammation. Corticosteroids like fluticasone are preferred, making this choice incorrect for optimal treatment.

Choice C reason: Propranolol, a beta-blocker, treats hypertension and cardiac conditions, not rhinitis. It has no effect on allergic inflammation, histamine, or nasal congestion. Its use in rhinitis could worsen symptoms by causing bronchoconstriction in asthmatics, making this choice inappropriate and incorrect.

Choice D reason: Fluticasone propionate, an intranasal corticosteroid, reduces inflammation, edema, and histamine effects in seasonal and perennial rhinitis. It targets the allergic cascade, decreasing nasal congestion, sneezing, and itching, making it the most effective and guideline-recommended treatment, thus the correct choice for rhinitis management.