The nurse is caring for a client with hepatic encephalopathy who is receiving lactulose. Which of the following findings would indicate that the medication has been effective?

Lactulose is used in hepatic encephalopathy to reduce ammonia levels by promoting its excretion through the stool. Improved mental status (A) indicates reduced ammonia toxicity, directly reflecting the medication's therapeutic effect. Looser stools (B) and reduced abdominal distension (C) are expected effects of lactulose but are secondary to the primary goal of ammonia reduction. Increased serum potassium (D) is incorrect, as lactulose does not directly affect potassium levels.