Exenatide, sold under the brand name Byetta and Bydureon among others, is a medication used to treat diabetes mellitus type 2. It is used together with diet, exercise, and potentially other antidiabetic medication. It is a treatment option after metformin and sulfonylureas. It is given by injection under the skin within an hour before the first and last meal of the day. A once-weekly injection version is also available.