What side effects may I notice from receiving Lactulose?

Side effects that you should report to your doctor or health care professional as soon as possible:
-diarrhea

Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):
-belching, flatulence
-nausea or vomiting
-stomach pain or discomfort

This list may not describe all possible side effects for Lactulose. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.