A nurse is reviewing the medical history of a client who has a new prescription for magnesium hydroxide. Which of the following conditions should the nurse report to the provider?

A. Metabolic acidosis: Magnesium hydroxide is an antacid and laxative that typically does not exacerbate metabolic acidosis. This condition does not require immediate notification. B. Renal failure: Magnesium is excreted by the kidneys, and impaired renal function increases the risk of hypermagnesemia, which can cause serious cardiac and neuromuscular complications. The provider should be notified before administration. C. Gastroesophageal reflux: Magnesium hydroxide is often used to relieve symptoms of gastroesophageal reflux. This condition is an appropriate indication, not a contraindication. D. Constipation: Constipation is another common indication for magnesium hydroxide use, and it does not require notifying the provider before administration.