Which laboratory value should be monitored in clients taking triamterene?

• A. Sodium levels
• B. Potassium levels
• C. Calcium levels
• D. Magnesium

Answer: (B)

Potassium balance is the key concept here. Triamterene is a potassium-sparing diuretic, meaning it reduces the kidney’s excretion of potassium in the distal tubule/collecting duct. By conserving potassium, it can raise blood potassium levels, leading to hyperkalemia. That’s why monitoring potassium is essential for clients on triamterene.

Know the signs of high potassium (muscle weakness, fatigue, paresthesias, and potentially dangerous heart rhythm changes) and the usual target range (about 3.5–5.0 mEq/L). This drug’s risk profile isn’t about calcium or magnesium changes as the primary concern, though these electrolytes can shift with various diuretics; the main issue with triamterene is preventing hyperkalemia through regular potassium checks and considering interactions with other potassium-raising medications.