Which statement about sodium bicarbonate as an antacid is true?

Which statement about sodium bicarbonate as an antacid is true?

• A. Causes metabolic acidosis
• B. Causes metabolic alkalosis
• C. Causes kidney stones
• D. Has no systemic effect

Answer: (B)

Sodium bicarbonate acts as a base and, when absorbed, raises the plasma bicarbonate level. It neutralizes gastric acid to form sodium chloride, water, and carbon dioxide, but the bicarbonate that enters circulation can increase buffering in the blood. If enough bicarbonate is absorbed or the kidneys can’t adequately excrete the excess, this shifts the body’s pH toward alkalosis, i.e., metabolic alkalosis. That’s why the statement about causing metabolic alkalosis is correct. It does not cause metabolic acidosis, and while the absorbed bicarbonate can have systemic effects, it’s not accurate to say it has no systemic effect. The notion of it causing kidney stones isn’t its primary or expected effect in this context.

Sodium bicarbonate acts as a base and, when absorbed, raises the plasma bicarbonate level. It neutralizes gastric acid to form sodium chloride, water, and carbon dioxide, but the bicarbonate that enters circulation can increase buffering in the blood. If enough bicarbonate is absorbed or the kidneys can’t adequately excrete the excess, this shifts the body’s pH toward alkalosis, i.e., metabolic alkalosis. That’s why the statement about causing metabolic alkalosis is correct.

It does not cause metabolic acidosis, and while the absorbed bicarbonate can have systemic effects, it’s not accurate to say it has no systemic effect. The notion of it causing kidney stones isn’t its primary or expected effect in this context.