GLP-1 medications after bariatric surgery

Navigating the Risks of GLP-1 Medications After Bariatric Surgery

June 5, 2024

Editor's note: "Navigating the Risks of GLP-1 Medications After Bariatric Surgery" by Patricia Hill is part one of a three-part series.

Recently, the use of GLP-1 receptor agonists, like Wegovy, Mounjaro, Ozempic, and Zepbound, has gained popularity as an effective treatment for weight management and type 2 diabetes.

We already know that bariatric surgery, which includes procedures like gastric bypass, sleeve gastrectomy, duodenal switch, and others, is a significant intervention aimed at reducing stomach size or altering the digestive process to facilitate weight loss. This surgery not only limits food intake but also induces hormonal changes that affect hunger and satiety, contributing to weight loss and improved metabolic health.

Because of the impact of bariatric surgery on the body, bariatric patients need to be particularly cautious and well-informed before starting any GLP-1 medication. In this first of a series of three articles, we are exploring the potential risks and considerations associated with using these medications after surgery.

Understanding GLP-1 Receptor Agonists

As we get older, our body makes fewer hormones, including GLP-1, which helps control blood sugar levels, keeps you feeling full after meals, and regulates insulin and glucagon production. This hormone drop can make it tricky for some adults to manage blood sugar and weight, possibly leading to other health issues.

Think of your body like a sugar factory: after eating, sugar goes into your blood, and GLP-1 hits the switches, telling your pancreas to make insulin, stopping your liver from making too much sugar, and telling your brain you're full, slowing down how fast your stomach empties.

Synthetic GLP-1 medications mimic this natural hormone, helping manage blood sugar and curb appetite. They're handy for type 2 diabetes and can be helpful for weight loss, especially when other methods haven't done the trick.

When Bariatric Surgery and GLP-1 Medications Meet

After bariatric surgery, the body undergoes significant changes in how it handles the digestion and absorption of food and medications. Adding GLP-1 medications into a body with an altered digestive system requires a careful approach for several reasons:


Altered Nutrient Absorption

Bariatric surgery changes the absorption of nutrients. GLP-1 medications can slow the emptying of the stomach, potentially worsening nutritional absorption. Regular monitoring and possibly adjusting dietary intake to prevent deficiencies is important.


Risk of Hypoglycemia

While GLP-1 medications typically have a low risk of causing low blood sugar, the combination of these drugs with bariatric surgery, especially in patients taking other diabetes medications, can increase this risk. Regular monitoring of blood glucose levels is crucial.


Gastrointestinal Side Effects

Both bariatric surgery and GLP-1 medications can cause gastrointestinal side effects such as nausea, vomiting, and diarrhea. When surgery is combined with these medications, the effects may be amplified, requiring adjustments in medication dosing or timing.


Weight Loss Synergy

Given that both bariatric surgery and GLP-1 medications both promote weight loss, there is a potential risk of rapid and/or excessive weight loss. This can lead to malnutrition, other serious health issues, and even long-term damage to the body if not carefully managed.


Long-term Effects and Monitoring

The long-term effects of combining bariatric surgery with GLP-1 medication therapy are not fully understood as there has not been adequate time to perform the necessary research. Continuous monitoring of weight, nutritional status, and metabolic health is necessary to ensure safe and effective outcomes.

Recommendations for Patients

For patients considering or currently using GLP-1 medications after bariatric surgery, the following recommendations are important:

  • Consultation and Monitoring: Regular follow-ups with your primary healthcare providers specializing in bariatric medicine are essential. They can assess the suitability of GLP-1 medications in your specific case, considering your surgery type, current health status, and weight management goals. Online pop-up companies peddling these drugs to cash in on a craze are NOT recommended.

  • Gradual Introduction: If a GLP-1 medication is deemed to be potentially beneficial, starting with a lower dose, and gradually increasing it can help mitigate gastrointestinal side effects and allow monitoring of any negative reactions or excessive / unhealthy weight loss.

  • Nutritional Guidance: Working with a nutrition expert who specializes in bariatric health to adjust your diet for potential changes in nutrient absorption and to manage side effects is crucial. Ensuring a balanced intake of nutrients to prevent deficiencies and support overall health is necessary. It’s essential that patients consume adequate calories in the right macro percentages for proper body function.

  • Awareness of Side Effects: Be very mindful about monitoring and reporting any side effects, especially gastrointestinal issues, to your primary healthcare provider. They may need to adjust your medication dose or regimen accordingly. Some side-effects can be managed through nutrition, as will be discussed in detail in the next two segments of this series.

  • Holistic Approach: As Oprah Winfrey insightfully shared in her televised special, Shame, Blame, and the Weight Loss Revolution, achieving health goals requires more than medication. It's a multi-pronged approach. Medication is just one part of a comprehensive weight management strategy. A healthy diet, regular physical activity, and psychological support are equally important to ensure long-term success.


While GLP-1 medications offer promising benefits for weight management and metabolic health, their use after bariatric surgery requires careful consideration and management. Understanding the potential risks and how to navigate them is crucial for ensuring safe and effective treatment. With the right guidance and monitoring, patients can achieve their health and weight goals post-bariatric surgery while minimizing the associated risks.

GLP-1 medications after bariatric surgery
Patricia Hill


Patricia Hill is the owner, health and wellness coach, and certified nutrition expert of My Bariatric Kitchen and GLP-1 Success (launching June 2024). Since having VSG surgery in 2016, she has helped thousands of patients learn how to eat right, establish new habits, and navigate life successfully after surgery through her subscription, MBK Monthly. For information, resources, and more, be sure to join her newsletter/email list, and follow her on Facebook and Instagram.