Rybelsus® tablets (semaglutide) is a prescription medicine used in adults with type 2 diabetes mellitus to decrease blood sugar levels. Rybelsus® can be prescribed when other diabetes medicines have been tried without success and should be used together with diet and exercise. Rybelsus® tablets work to lower blood sugar (glucose) levels by increasing how much insulin is released and decreasing glucagon secretion. This medicine also may slow gastric emptying after eating.