What is the best diabetes drug for weight loss?

How do weight loss drugs work | Best diabetes drug for weight loss | Benefits of GLP-1s | Side effects | Who should take diabetes drugs | Contraindications | Insurance coverage

Weight loss is no easy feat—sometimes, a reduced-calorie diet and exercise are not enough to lead to significant change. And you may not want to take the leap to bariatric surgery. Enter a new(-ish) class of drugs originally developed for diabetes with the side effect of weight loss. This drug class is known as glucagon-like peptide-1 (GLP-1) agonists and contains several FDA-approved medications. Drugs in this class, such as Ozempic, Trulicity, and Victoza, were initially developed to be used along with lifestyle changes like diet and exercise to control blood sugar levels (blood glucose levels) in adults with Type 2 diabetes. Some of these medications are also used in patients with heart disease (cardiovascular disease) to reduce the risk of cardiovascular events, like a heart attack or stroke. However, as more and more evidence shows that these prescription drugs promote weight loss, health professionals are increasingly prescribing them for the off-label use of chronic weight management in patients who do not have diabetes. 

What are these drugs, and could they work for you? Continue reading to learn more about GLP-1 agonist drugs, also called GLP-1s or GLP-1 receptor agonists.  

How do weight loss drugs work? 

GLP-1 agonists, such as Ozempic, work in three ways:

• When blood sugar is high, they stimulate insulin secretion (production), which helps control blood sugar.
• When blood sugar is high, they inhibit glucagon secretion (production), which helps control blood sugar.
• They also cause slowed gastric emptying (delayed gastric emptying), which helps control blood sugar—but also helps you feel satisfied with less food and decreases appetite and cravings, which enables you to stick to a healthy eating plan.

These drugs are not stimulants (like phentermine) and do not speed up your metabolism. 

In addition to GLP-1 agonists, there is also Mounjaro to consider. Mounjaro (tirzepatide) is the first glucose-dependent insulinotropic polypeptide receptor and glucagon-like peptide-1 agonist (also called GLP-1 and GIP receptor agonists) and works similarly to GLP-1 agonists. Mounjaro is currently approved with diet and exercise to improve blood sugar control in patients with Type 2 diabetes, but it is being studied for weight loss. The United States Food and Drug Administration (FDA) has assigned Mounjaro a Fast Track designation for this use. 

Healthcare providers prescribe these medications to people to lose weight, even if they don’t have diabetes. This increased prescribing is because studies have shown people lose a significant amount of weight when they take a drug in the GLP-1 agonist drug class. 

What is the best diabetes drug for weight loss?

There is not necessarily one best treatment option for weight loss. There are several effective therapeutic options for weight loss in the GLP-1 agonist drug class. The best diabetes drug for weight loss is the one that works best for you, with the least amount of side effects. To determine which, if any, diabetes drug is best for you, speak with your healthcare provider. The chart below outlines the most common GLP-1 agonists (including Mounjaro) that are prescribed off-label for weight loss. All but Rybelsus are injectable drugs administered subcutaneously (under the skin) of the stomach, upper arm, or thigh with a pen injector device. Although most are injected, they are not to be confused with insulin. Ozempic and Mounjaro are most frequently in the news, in high demand (leading to shortages), and even viral on social media, but any medication in this drug class may cause appetite and weight loss. 

*This chart does not include GLP-1 agonists specifically approved for weight loss (not diabetes), including Saxenda and Wegovy.

Benefits of GLP-1 drugs for weight loss

Generally, people taking a GLP-1 can expect to lose 3 to 5% of body weight at the dosage for diabetes. This means someone who weighs 200 pounds may lose about 6 to 10 pounds. However, higher doses may lead to more weight loss. 

Although any GLP-1 drug can promote weight loss, let’s look at some clinical studies and their findings. 

• The SURPASS-1 clinical trial studied Mounjaro in people with diabetes and found that the medication reduced hemoglobin A1C (a measure of long-term blood sugar control) and resulted in significant weight loss of about 14 to 19 pounds. Additional SURPASS trials confirmed that Mounjaro reduced A1C levels and promoted considerable weight loss. 
• In the SURMOUNT-1 clinical trial for Mounjaro, people who had obesity or were overweight but did not have diabetes took either Mounjaro or a placebo (inactive medication). Participants’ mean weight loss percentage after 72 weeks was 15% with 5 mg weekly doses, 20% with 10 mg weekly doses, and 21% with 15 mg doses, compared to 3% in participants who received a placebo. Eighty-five percent of participants lost 5% or more of their body weight, compared to 35% who took a placebo. Additional SURMOUNT trials are still in progress. 
• The SUSTAIN trials studied semaglutide, the ingredient in injectable Ozempic and oral Rybelsus. It’s also the ingredient in Wegovy, which is approved for weight loss but not diabetes. The first SUSTAIN trial found that semaglutide, injected once weekly, significantly decreased A1C. People who took semaglutide lost about eight to 10 pounds over 30 weeks, compared to about 2 pounds in those who took a placebo. Additional SUSTAIN trials confirmed that semaglutide significantly reduces A1C and weight (some participants lost up to about 13 pounds, or 15 pounds with a higher dose) and lowers cardiovascular risk.

Side effects of diabetes medications for weight loss

With any drug comes a risk of side effects. The most common side effects of Ozempic and other GLP-1 agonist medications are gastrointestinal side effects, including:

• Nausea
• Vomiting
• Constipation or diarrhea
• Indigestion 
• Stomach pain
• Reflux
• Burping
• Gas

These side effects can range from mild to severe and may gradually disappear as your body adjusts to the medication. If these side effects are troublesome and persist, consult your healthcare provider. 

Other common side effects may include injection site reactions and diabetic retinopathy. 

The risk of hypoglycemia (low blood sugar) is low unless a GLP-1 agonist is combined with insulin or certain oral diabetes drugs such as glipizide, glimepiride, or glyburide. In this case, close monitoring of blood glucose levels is required, and a dosage adjustment of insulin or the oral diabetes drug may be necessary. 

All GLP-1 agonists (this includes tirzepatide, or the brand name Mounjaro) have a black box warning, the most serious warning required by the FDA. The warning states that GLP-1 agonist medications have caused thyroid cancer in animal studies. It is not known if this applies to humans. People with a personal or family history of medullary thyroid carcinoma (MTC) or who have Multiple Endocrine Neoplasia syndrome type 2 (MEN 2) should not take a GLP-1 agonist. All individuals who take a GLP-1 agonist should be alert to symptoms of a thyroid tumor, including hoarseness, a lump in the neck, and difficulty swallowing or breathing. 

Other serious side effects may include pancreas, gallbladder, and kidney problems, including kidney failure. In rare cases, severe allergic reactions may occur. Patients who experience symptoms of an allergic reaction, such as hives, difficulty breathing, or swelling of the face, lips, tongue, or throat, should seek emergency medical help. 

This is not a complete list of side effects, and others may occur. Consult your healthcare provider for more information and questions about side effects. 

Who should take diabetes weight loss drugs?

If you want to take a diabetes medication, such as Ozempic, for weight loss, visit your healthcare provider. Together, you can determine if you are an appropriate candidate for this medication. Candidates may include people with a body mass index (BMI) of 30 kg/m2 or higher, or people with a BMI of 27 kg/m2 or higher, with a weight-related medical condition like high cholesterol or blood pressure. 

In addition to people with diabetes or who need to lose weight, these medications should also be considered in individuals who do not have heart disease but are at high risk for heart disease, such as those with high blood pressure and obesity. A new study published in February 2023 found that most Americans with Type 2 diabetes are candidates for newer medications such as GLP-1s (or a medication from another drug class called SGLT2 inhibitors), but few are taking them. Although 82% of adults in the U.S. with Type 2 diabetes qualified for a GLP-1 or SGLT2 medication, only about 10% of those took one of the drugs. 

Dr. Robert Gabbay, chief medical officer and chief scientific officer of the American Diabetes Association (ADA), notes that certain diabetes drugs, including GLP-1s, can significantly lower the risk of heart and kidney disease.

Who should NOT take diabetes weight loss drugs?

Certain individuals should not take medications like Ozempic, Wegovy, or Mounjaro for weight loss (or diabetes). People who should not use these medications include:

• Individuals who are allergic to the specific medication or any drug in the GLP-1 agonist class
• Individuals with a history or family history of medullary thyroid carcinoma
• Individuals with Multiple Endocrine Neoplasia syndrome type 2 (MEN 2) 
• Individuals with Type 1 diabetes

In some cases, a GLP-1 agonist may or may not be appropriate and, if prescribed, must be used with caution. This includes people with kidney problems, pancreas problems, diabetic retinopathy, and women of childbearing age.

Healthcare professionals will review medical conditions, medical and family history, health concerns, and other factors to consider appropriate candidates for diabetes medication for weight loss. 

Does insurance cover weight loss drugs? 

Private insurance companies, Medicaid, or Medicare prescription plans may or may not cover these medications. Prior authorization may sometimes be required before a coverage determination is made. 

You can contact your insurance provider for the most up-to-date coverage information on these drugs. 

If your insurance does not cover your weight loss medication, you can always use a free SingleCare card or coupon to save up to 80% off the cost of your medicine. What’s more, SingleCare discounts are reusable, so you can use them on your refills to save considerably throughout the year.