Are there any type 2 diabetes drugs that can help people lose weight and lower their blood sugar? Are there side effects?

Answer From M. Regina Castro, M.D.

There's a class of type 2 diabetes drugs called incretin mimetics or glucagon-like peptide 1 (GLP-1) agonists that are taken by injection, but aren't insulin. These medications not only improve blood sugar control but may also lead to weight loss.

Depending on the medication and the dose, weight loss may average about 3 to 5.5 pounds (1.5 kilograms, or kg, to 2.5 kg) when using these drugs. If you're actively trying to lose weight through lifestyle changes and the use of one of these medications, research has shown that the drugs may lead to around 6 to 9 pounds (2.8 kg to 4.2 kg) of additional weight loss.

Drugs in the class include:

  • Dulaglutide (Trulicity), taken weekly
  • Exenatide extended release (Bydureon), taken weekly
  • Semaglutide (Ozempic), taken weekly
  • Liraglutide (Victoza), taken daily
  • Lixisenatide (Adlyxin), take daily
  • Exenatide (Byetta), taken twice daily

These medications improve blood sugar control by mimicking the action of a hormone called glucagon-like peptide 1 (GLP-1). Among other things, these drugs stimulate insulin secretion in response to rising blood sugar levels after a meal, which results in lowering of the blood sugar.

There are many proposed ways in which these medications cause weight loss. One is that they appear to help suppress appetite.

But the most prominent effect of these drugs is that they delay the movement of food from the stomach into the small intestine. As a result, you may feel "full" faster and longer, so you eat less.

In addition to helping with control of blood sugar and with weight loss, this class of medications may also improve your heart health. Some drugs in this class of medications appear to lower the risk of heart disease-related death, research suggests. People taking these drugs have seen improvements in their blood pressure, cholesterol and triglyceride levels, though it's not clear whether these benefits are from the medicine or the weight loss.

The downside to these drugs is that they have to be taken by injection, and they also have a risk of side effects, some serious. The more common side effects may improve after you've taken the medication for a while. Some of the more common side effects include:

  • Nausea
  • Vomiting
  • Diarrhea

Low blood sugar levels (hypoglycemia) are also a risk, but usually only if you're taking another medication known to lower blood sugar.

This class of drugs isn't recommended if you have a personal or family history of medullary thyroid cancer or multiple endocrine neoplasia. Laboratory studies have linked these drugs with thyroid tumors in rats, but until more long-term studies are completed, the risk to humans isn't known. They're also not recommended if you've had pancreatitis.

The drugs already discussed are designed for people who have type 2 diabetes. There is also a drug that contains a higher dose of liraglutide (Saxenda) that's approved for the treatment of obesity in people who don't have diabetes.

If you have diabetes and wonder if one of these drugs may be helpful for you, talk to your doctor.


M. Regina Castro, M.D.

May 11, 2018 See more Expert Answers