WHAT TO TRY FIRST
The 2015 American Diabetes Association guidelines and the British National Health Service recommend that everyone with diabetes start with:
If diet and exercise alone have not controlled blood sugar enough, metformin is the first-choice drug.
WHAT ELSE TO TRY
The 2015 American Diabetes Association guidelines recommends adding another diabetes medication If metformin at the highest dose does not control blood sugar enough or causes too many side effect. They recommend adding: another pill (sulfonylurea such as glipizide, thiazolidinedione (pioglitazone), DPP-4 inhibitor such as sitagliptin, SGLT2 inhibitor such as canaglifozin), GLP-1 receptor agonist injections such as exenatide or long-acting insulin. The British National Health Service recommends a sulfonylurea as the first-choice medication to add.
While the American Diabetes Association says that people who cannot take metformin can start with any diabetes medications, the British National Health Service suggest starting with a sulfonylurea.
American Diabetes Association. Clinical Practice Recommendations 2015. Published January 2015.
National Institute for Health Care Excellence (NICE). Type 2 diabetes: The management of type 2 diabetes. Published May 2009.