If GLP-1 medications seem as pervasive in conversation and advertising as aspirin and cold medicine these days, that’s because they are. The number of Americans taking these medications has roughly doubled in just two years — from around five million in 2023 to roughly 10 million today.

When used appropriately, these medications are highly effective in aiding weight loss and improving blood sugar levels — and recent research continues to uncover new benefits.

What are GLP-1 medications, exactly?

GLP-1 stands for glucagon-like peptide-1, a metabolic hormone released by the gut (commonly called an incretin hormone). It is normally produced in response to food intake and plays a role in insulin secretion, gastric emptying and reducing appetite. GLP-1 receptor agonist (GLP-1 RA) medications mimic this hormone. These medications have become widely known as GLP-1s, a shorthand we’ll use throughout this article.

What are the benefits of GLP-1 medications?

GLP-1s are approved by the Food and Drug Administration (FDA) for chronic weight management and Type 2 diabetes. In addition to these approved uses, clinical trials in people with specific health conditions have shown that GLP-1s offer additional benefits, such as:

• Reducing the risk of heart attack and stroke
• Slowing kidney disease progression
• Treating moderate-to-advanced liver fibrosis
• Treating moderate-to-severe obstructive sleep apnea

Also, semaglutide (Wegovy) is FDA-approved for chronic weight management in adolescents age 12 and older with obesity. Dulaglutide (Trulicity) is FDA-approved for Type 2 diabetes in adolescents age 10 and older.

Who is a good candidate for GLP-1?

You may be a good candidate if you are an adult with Type 2 diabetes who also has one of the following:

• Heart disease or multiple risk factors for heart disease
• Chronic kidney disease
• A body mass index (BMI) over 27 (This means your weight is generally higher than what’s considered healthy for your height.)

For weight management, you may be a good candidate if you are an adult with:

• A BMI over 30
• A BMI over 27 with one weight-related condition, such as:
  
  • High blood pressure
  • High cholesterol
  • Type 2 diabetes

Who should not take a GLP-1 medication?

You should not take a GLP-1 if you have had:

• A personal or family history of medullary thyroid cancer
• Multiple endocrine neoplasia Type 2 (MEN2)
• A history of pancreatitis due to unknown causes
• You are pregnant or breastfeeding

What is the difference between pill form and injection?

GLP-1s come in many different brands and formulations. The same active ingredient may be marketed differently according to the FDA-approved indication or formulation. For example, semaglutide is available as two injectables:

• Wegovy for weight loss
• Ozempic for Type 2 diabetes

It is also available as two oral tablets:

• Wegovy pill for weight loss
• Rybelsus for Type 2 diabetes

The dosing schedule also varies by indication, depending on how the medication was studied in clinical trials.

Oral medications are often preferred by patients, but injectable GLP-1s are generally more effective at aiding weight loss and lowering blood sugar.

Current studies are evaluating whether higher doses of oral GLP-1s can close this gap — an important development for people who are averse to injections.

Some oral formulations also come with strict administration requirements. For example, Rybelsus and Wegovy must be taken on an empty stomach, 30 minutes before eating, drinking or taking other medications.

Switching between oral and injectable GLP-1s is possible and commonly done based on clinical results, tolerability or insurance coverage.

What are some of the side effects?

GLP-1s slow the movement of food through the stomach and intestines, which is why the most common side effects are gastrointestinal: nausea, diarrhea, constipation and vomiting. To minimize these affects you can:

• Eat smaller meals or snacks instead of large meals
• Eat more slowly
• Reduce intake of high-fat and spicy foods
• Drink more water

If you are currently taking a GLP-1 and considering an increase in the dosage, have your doctor evaluate your ability to tolerate it. If you have lingering gastrointestinal side effects, consider waiting to increase the dose, or increasing the dosage more slowly.

Important side effects that warrant immediate attention by a doctor include persistent vomiting, diarrhea and/or abdominal pain. Left unaddressed, these conditions can lead to dehydration and acute kidney injury.

Is long-term use safe?

The long-term safety of GLP-1s is still being established, but emerging research has begun to highlight several areas of concern. A systemic review and meta-analysis of clinical trials found that GLP-1 use was associated with an increased risk of gallbladder and biliary diseases — particularly at higher doses and with longer use.  Bone density loss may be associated with long-term GLP-1 use, although findings are still inconclusive. There is also some evidence that the medication may contribute to worsening retinopathy, a disease affecting the retina.

For these reasons, talk with your doctor about using a GLP-1. They will review your medical and family history to determine if the medication is right for you.

Is it safe to buy a GLP-1 medication from an online site?

Unfortunately, the growing popularity of GLP-1s has attracted marketing schemes that can put your safety at risk. There have been many reports of compounded and counterfeit GLP-1s causing serious harm due to dosing inaccuracies and impurities. Some websites have scammed patients by accepting payment and never delivering medications.

To reduce the risk of harm, only obtain a prescription for these medications (or any medication) from licensed professionals and licensed pharmacies. You can verify licensing online through your state or through the FDA’s BeSafeRx website.

Talk to an expert about balanced nutrition

Whether you are pursuing a GLP-1 for weight loss or diabetes management, it is highly recommended that you work with a registered dietitian to focus on lifestyle modifications. Maintaining adequate caloric intake is essential to ensure balanced nutrition while on therapy.