Which adverse effect can occur with sodium bicarbonate antacids?

• A. Metabolic acidosis
• B. Metabolic alkalosis
• C. Edema
• D. Hyperkalemia

Answer: (C)

Sodium bicarbonate antacids introduce a significant amount of sodium into the body. That extra sodium causes the body to retain water, increasing extracellular fluid volume. In people with reduced kidney function or other conditions like hypertension or heart failure, this sodium and water retention shows up as edema. This fluid overload is the most characteristic adverse effect of sodium-containing antacids. While excessive dosing can lead to metabolic alkalosis due to the extra bicarbonate, the edema from sodium load is the key, commonly observed risk. Hyperkalemia is not typically associated with these agents.