A nurse in a provider's office is reviewing the laboratory results of four clients who take digoxin.

Which of the following clients is at risk for developing digoxin toxicity?

The correct answer is Choice A: Dull, aching calf pain.

Choice A rationale:

Dull, aching calf pain is a common symptom of deep vein thrombosis (DVT), which can occur postoperatively, especially after vascular surgery. This pain is often due to a blood clot forming in the deep veins of the leg.

Choice B rationale:

Positive Kernig's sign is associated with meningitis and not typically related to thrombus formation.

Choice C rationale:

Soft, pliable calf muscle is not indicative of a thrombus. A thrombus would more likely cause tenderness and swelling.

Choice D rationale:

Positive Homan's sign (pain in the calf upon dorsiflexion of the foot) can be an indicator of DVT, but it is less reliable than dull, aching calf pain.

Choice A rationale:
A client who takes glyburide for type 2 diabetes mellitus is not at significant risk for developing digoxin toxicity. Glyburide is an antidiabetic medication and does not interact directly with digoxin.

Choice B rationale: Furosemide, a loop diuretic, can cause electrolyte imbalances such as hypokalemia (normal potassium levels: 3.5 to 5.0 mEq/L) and hypomagnesemia (normal magnesium levels: 1.7 to 2.2 mg/dL). These imbalances increase the sensitivity to digoxin and the risk of toxicity. Digoxin toxicity is associated with symptoms like nausea, vomiting, and arrhythmias. Furosemide's impact on electrolytes makes it a significant risk factor for digoxin toxicity.

Choice C rationale: Cimetidine, a histamine H2 receptor antagonist, can inhibit the metabolism of certain drugs by affecting liver enzymes. However, it does not significantly alter digoxin levels or increase the risk of toxicity. Normal liver enzyme levels include ALT (7 to 56 U/L) and AST (10 to 40 U/L). While cimetidine may interact with other medications, its effect on digoxin is minimal.

Choice D rationale:
A client who takes azelastine for allergic rhinitis is not at significant risk for developing digoxin toxicity. Azelastine is an antihistamine and does not interact directly with digoxin.