Understanding The Potential Side Effects of GLP-1 for Weight Loss

With obesity rates continuing to rise worldwide, new tools in weight management have become essential in the fight against obesity-related health complications. Among the latest advancements are GLP-1 receptor agonists, a class of medications originally developed to treat type 2 diabetes, which are now popular for their significant weight loss benefits. Medications like semaglutide and tirzepatide have shown promising results, leading to their use as weight-loss treatments and opening doors for millions struggling to achieve or maintain a healthy weight.

While effective, these medications come with a range of potential side effects that patients should be aware of before beginning treatment. Knowing what to expect can help patients manage these effects and approach their weight-loss journey with confidence and caution.

What Are GLP-1 Medications?

GLP-1 receptor agonists are drugs that mimic the function of glucagon-like peptide-1 (GLP-1), a hormone produced in the gut that has multiple roles in regulating blood sugar levels and appetite. GLP-1 helps slow the rate at which the stomach empties, promotes a feeling of fullness, and signals to the brain to reduce food intake. For people with obesity, these effects can be instrumental in helping reduce caloric intake and achieve sustainable weight loss.

Commonly prescribed GLP-1 medications for weight management include:

• Semaglutide (brand names include Ozempic and Wegovy)
• Tirzepatide (brand names include Mounjaro)
• Liraglutide (brand names include Saxenda and Victoza)

In addition to aiding in weight loss by reducing appetite, these medications can also improve blood glucose control, which is beneficial for individuals with or at risk for type 2 diabetes.

Studies show that patients taking GLP-1 medications for weight loss can experience a reduction in body weight by 10-15% over a period of several months when combined with lifestyle interventions such as a healthy diet and exercise; however, patients must be mindful of the potential side effects.

Common Side Effects

While GLP-1 medications can be effective, they are not without side effects. Understanding the common side effects helps patients recognize what’s normal and when they may need additional support.

Gastrointestinal Symptoms

Gastrointestinal (GI) issues are the most frequently reported side effects of GLP-1 medications. These include:

• Nausea: This is the most common side effect, affecting approximately 20-40% of patients initially. Nausea may be more pronounced at the beginning of treatment and may lessen as the body adjusts.
• Vomiting: A smaller percentage of patients experience vomiting, especially when doses are increased too quickly.
• Diarrhea: Some individuals experience diarrhea, particularly after eating high-fat or spicy foods, which can exacerbate GI symptoms.
• Constipation: Contrarily, some people report constipation, which can result from reduced food intake and slower gastric emptying.

Fatigue

Fatigue is another reported side effect, though its underlying cause is not completely understood. Some experts suggest that the caloric deficit induced by reduced appetite could contribute to feelings of tiredness, as well as shifts in hormone levels. Fatigue may be temporary as the body adapts to new dietary habits and reduced caloric intake.

Headaches

Headaches are a less common but notable side effect, potentially linked to dehydration, dietary changes, or the body’s adjustment to GLP-1 medications. Patients are encouraged to stay hydrated, as dehydration can exacerbate headaches and contribute to other adverse effects.

Less Common but Noteworthy Side Effects

While most side effects from GLP-1 medications are mild and manageable, some patients may experience more serious side effects that require close monitoring.

Gallbladder Issues

Rapid weight loss can increase the risk of gallbladder issues, including gallstones. Studies suggest that people who lose weight quickly, particularly with the aid of medications like GLP-1 receptor agonists, may have a higher likelihood of developing gallstones, which can cause severe abdominal pain and may require surgical intervention.

Pancreatic Cases

GLP-1 medications have been associated with pancreatitis, an inflammation of the pancreas. Symptoms include severe abdominal pain, vomiting, and fever. While the incidence of pancreatitis is low, patients should report any abdominal discomfort to their healthcare provider to ensure early detection and prevent complications.

Kidney Concerns

Dehydration due to vomiting or diarrhea can strain the kidneys, especially in individuals with pre-existing kidney conditions. Prolonged dehydration can reduce kidney function and may increase the risk of acute kidney injury. Patients are advised to drink plenty of water, particularly during periods of GI upset, to maintain hydration and kidney health.

Managing and Minimizing Side Effects

Taking a proactive approach to managing side effects can make a significant difference in a patient’s experience with GLP-1 medications. Here are some strategies to consider:

• Start low, go slow: Starting with a low dose and gradually increasing it allows the body to adjust, potentially reducing nausea and other GI issues. This approach is especially helpful for minimizing early treatment-related discomfort.
• Stay hydrated: Proper hydration can help manage headaches and reduce kidney-related risks. Aim for at least eight glasses of water per day, adjusting as needed based on individual symptoms and healthcare provider recommendations.
• Balanced nutrition: A balanced diet rich in fiber, lean protein, and whole grains can support digestive health and help reduce constipation. Limiting high-fat and spicy foods may also lessen nausea and diarrhea.
• Regular check-ups: Ongoing healthcare provider monitoring allows for tailored advice and adjustments. Patients are encouraged to communicate any persistent or severe symptoms promptly for appropriate intervention.

When to Contact a Healthcare Provider

Patients should know which symptoms require immediate medical attention. Severe side effects that warrant contacting a healthcare provider include:

• Severe abdominal pain: This could be a sign of pancreatitis or gallbladder issues, which require immediate evaluation.
• Persistent vomiting: Prolonged vomiting can lead to dehydration and electrolyte imbalances.
• Changes in urination: A decrease in urination or dark urine may indicate dehydration or kidney strain, especially in individuals with pre-existing kidney issues.

Regular check-ins with a healthcare provider are essential to ensure that the treatment is both effective and safe. Individualized care enables providers to adjust doses, recommend dietary changes, and address any complications as they arise.

GLP-1 medications offer an effective approach for individuals seeking substantial weight loss support. Despite their popularity, patients need to understand the side effects associated with these drugs. Most side effects are manageable and may decrease with time, while others may require more attention. With guidance from healthcare professionals and a proactive approach, many patients find GLP-1 medications an invaluable tool in their weight-loss journey.

As with any treatment, it is essential to weigh the potential benefits against the risks. Consulting a healthcare provider helps ensure that GLP-1 medications are the right fit, allowing patients to embark on their weight-loss journey informed and prepared for success.

Dr. Gordon is Board Certified by the American Board of Dermatology and is a member of the American Society of Dermatologic Surgery (ASDS), the American Academy of Dermatology, the Dermatology Foundation, the Texas Medical Association and the Travis County Medical Society. Currently, Dr. Gordon oversees our South Austin location.