Duphalac is a lactulose oral solution (667 g/l) used to treat constipation. This 300ml syrup works by drawing water into the bowel to soften stools and make them easier to pass, providing gentle and effective relief from constipation. Duphalac contains lactulose as its active ingredient, which is a type of sugar that cannot be digested by the body. It works by pulling water into the large intestine (colon) to soften hard stools. This medication typically starts working within 24-48 hours. As with all medications, use only as directed by your healthcare provider and read all warning labels carefully before use. Store at room temperature away from direct sunlight.