Duphalac is a 300ml oral solution containing lactulose (667 g/l). It is a medicinal syrup commonly used as a laxative treatment to help regulate bowel movements and treat constipation. Duphalac comes in a 300ml bottle containing lactulose oral solution at a concentration of 667 g/l. As this is a medicinal product, please consult your healthcare provider regarding proper dosage, usage instructions, and potential side effects before use.