 It's a once-daily pill that helps you get ahead of your symptoms. It's proven to help you have more frequent and complete bowel movements and helps relieve overall abdominal symptoms, belly pain, discomfort, and bloating. These symptoms were studied in combination, not individually. Do not give Linzess to children less than two. It may harm them. Do not take Linzess if you have a bowel blockage. Get immediate help if you develop unusual or severe stomach pain, especially with bloody or black stools. The most common side effect is diarrhea, sometimes severe. If it's severe, stop taking Linzess and call your doctor right away.