1. Constipation: It is often used to treat chronic constipation, a condition in which a person experiences difficulty passing stools or infrequent bowel movements. Lactulose works by drawing water into the bowel, softening the stool, and making it easier to pass.

2. Hepatic Encephalopathy: The medication is also used to treat hepatic encephalopathy, a condition in which the liver is unable to remove toxins from the blood, leading to a buildup of ammonia in the blood. It works by reducing the amount of ammonia in the blood and improving brain function.

Please note that this medication should only be taken as prescribed by your healthcare provider, and should not be used for self-diagnosis or self-treatment. It is important to follow the recommended dosage and duration of treatment to avoid any potential side effects or complications.