It’s no secret that GLP-1 medications like Ozempic, Wegovy, and Saxenda have become increasingly popular for weight loss. While these medications can be highly effective for managing conditions like MASLD, diabetes, and metabolic conditions associated with being in a larger body, they are not without risks. Unfortunately, many individuals are using GLP-1 inhibitors to facilitate weight loss when it isn’t medically necessary, exposing them to potential side effects without clear benefits. One risk that has gained attention with these medications is their possible link to gastroparesis or delayed stomach emptying.
As a registered dietitian, I frequently get asked about the risks of these types of medications causing gastroparesis. What are the chances I would get gastroparesis from taking a GLP-1 medication? In this post, we’ll break down what the research says, how these drugs affect digestion, and what you should know if you’re experiencing symptoms like bloating, nausea, or prolonged fullness.
Table of Contents
- What Are GLP-1 Inhibitors?
- Understanding Gastroparesis
- How GLP-1 Inhibitors Impact Gastroparesis
- Temporary vs. Long-Term Gastroparesis
- Best Diet for Gastroparesis
- Micronutrient Deficiencies on GLP-1 Inhibitors
What Are GLP-1 Inhibitors?
You may see these medications referred to as both GLP-1 receptor agonists and GLP-1 inhibitors, which can be confusing. Ultimately, the term “GLP-1 receptor agonist” is the more scientifically accurate name for the processes involved. However, we often refer to them as “GLP-1 inhibitors” more casually. But just so you know – we’re talking about the same thing!
To fully understand what these medications do, it is important to first learn what GLP-1 is. Glucagon-like peptide-1 (GLP-1) is a hormone that plays a crucial role in regulating blood sugar and appetite. When we consume food, this hormone is released by the intestines and helps to manage glucose levels via a few key mechanisms:
- Promoting Insulin Secretion – When blood sugar rises after eating, GLP-1 stimulates the pancreas to release insulin, helping lower glucose levels.
- Slowing Gastric Emptying – These medications delay the rate at which food leaves the stomach, leading to prolonged feelings of fullness and steadier blood sugar levels.
- Reducing Appetite – GLP-1 also acts on the brain to decrease hunger signals, often leading to reduced calorie intake and potential weight loss.
Given the powerful role of this hormone, it’s no surprise that researchers developed medications to target it for diabetes management – and later, for weight loss. However, it’s important to remember that these drugs were originally designed specifically for individuals with diabetes. Now, they are increasingly being used for weight loss, often in cases where it isn’t medically indicated.
Common GLP-1 Inhibitors
Some of the most commonly prescribed GLP-1 inhibitors include:
- Semaglutide (Ozempic, Wegovy, Rybelsus)
- Liraglutide (Victoza, Saxenda)
- Dulaglutide (Trulicity)
- Tirzepatide (Mounjaro)
- Exenatide (Byetta, Bydureon)
These medications are most commonly administered in the form of weekly injections, but there are a few oral formulations available on the market as well.
Understanding Gastroparesis
Gastroparesis is a disorder where the stomach takes longer than normal to empty food into the small intestine. This happens because the stomach muscles don’t work properly and efficiently. The job of the stomach is to both physically and chemically break down food. It acts a lot like a blender, as it grinds and mashes the material that we eat. In someone with gastroparesis, this ‘blender’ is much less powerful and therefore takes a greater amount of time to do its job.
This delay in the action of the stomach can lead to symptoms like nausea, vomiting, bloating, early fullness, and abdominal pain. Gastroparesis can be caused by diabetes, nerve damage, other underlying health conditions, and of course certain medications (the topic of this post!)
Gastroparesis is typically diagnosed via a test called a gastric emptying study. This test involves eating a small meal containing a trace amount of radioactive material while a scanner tracks how quickly food leaves your stomach. If more than 60% of the meal is retained in the stomach after 2 hours or 10% of the meal is retained after 4 hours, this is indicative of gastroparesis.
How GLP-1 Inhibitors Impact Gastroparesis
The research on GLP-1 inhibitors is pretty clear that taking these medications does slow gastric emptying. It’s part of the mechanism behind the effectiveness of these drugs – to contribute to a reduced appetite.
At this point, we don’t have a lot of high-quality, large-scale studies to show just how common gastroparesis is in patients on GLP-1 inhibitors. One of the biggest challenges when figuring out these statistics is the fact that both diabetes and GLP-1 inhibitors can result in delayed gastric emptying. Because much of the research is done in the diabetic population, it’s hard to get a true idea of what role medications like ozempic or saxenda have in inducing gastroparesis.
However, there are several case reports (ie. individual reports from doctors and researchers) where people have developed medication-induced gastroparesis while being on these drugs. In these reports, other potential causes of gastroparesis have been ruled out. That said, being on a GLP-1 inhibitor does not automatically mean someone will develop gastroparesis.
In general, care should be taken for individuals with pre-existing GI conditions, as they may be at higher risk for worsening symptoms. Additionally, proper education is crucial before starting these medications. Unfortunately, they tend to be over-prescribed and poorly communicated, leaving many patients unaware of potential side effects or how to properly use them for long-term success.
Temporary vs. Long-Term Gastroparesis
While GLP-1 inhibitors can slow stomach emptying, this effect does not necessarily indicate long-term gastroparesis. These medications work by delaying digestion, which can lead to symptoms like early fullness, nausea, and bloating. However, GLP-1 inhibitors have a long half-life – approximately five weeks. This refers to the amount of time it takes for half of the drug to be eliminated from the body. Since GLP-1 inhibitors have a half-life of about five weeks, it can take a few months for them to be fully cleared.
In general, if someone is struggling to meet their nutrition needs while on a GLP-1 inhibitor, stopping the prescription may be necessary. It’s important to allow sufficient time for the medication to clear from the body before assuming a diagnosis of gastroparesis. Symptoms often resolve once the medication is stopped. This waiting period helps differentiate between temporary medication effects and a more persistent digestive disorder. If symptoms continue beyond this timeframe, your doctor may recommend additional testing to assess stomach function.
What is the Best Diet for Gastroparesis?
When managing gastroparesis or symptoms of delayed gastric emptying, dietary adjustments play a crucial role in reducing discomfort and supporting digestion. While there is no single “best” diet for everyone with gastroparesis, there are certain strategies that can help improve symptoms.
A great starting point is understanding how different types of foods digest. When the stomach isn’t working at full capacity, opting for foods that require minimal effort to break down can make a significant difference. Here are some of my top tips for managing gastroparesis:
Choose foods that are low in fat and fibre
High fat and high fiber foods tend to slow digestion and can be harder for the stomach to process. Insoluble fibre in particular, which is found in lots of skins, seeds, and raw veggies is more challenging to break down. Opting for a more ‘GI Gentle’ diet can often be helpful, focusing on:
- Lean proteins like poultry, fish, eggs, and tofu
- Nut butters instead of whole nuts and seeds
- Well-cooked vegetables with a low to moderate fiber content (e.g., peeled zucchini, carrots, potatoes)
- Soft, easily digestible fruits (e.g., bananas, canned peaches, applesauce, melon)
- White bread, refined grains, pasta, and rice
Eat small, frequent meals
Large meals can overwhelm a sluggish stomach and worsen symptoms of bloating, nausea, and overfullness. Eating smaller meals more frequently throughout the day can help prevent excessive fullness and discomfort.
Adjust food consistency as needed
While this isn’t always necessary, opting for soft or blended foods can improve digestive comfort. Compared to solid foods, options like soups, smoothies, and porridge are often easier to tolerate. If meeting calorie needs becomes a challenge, nutritional shakes or liquid meal replacements can be a useful addition.
Consider meal timing and movement
Managing gastroparesis isn’t just about what you eat, but also how and when you eat. For instance, lying down immediately after eating can worsen symptoms like acid reflux, bloating, and indigestion because gravity isn’t helping to move food through the digestive tract. By remaining upright for at least 1-2 hours after eating, you allow your body to naturally digest the meal. Some people also find that getting up to move after eating is helpful. The act of walking around gently after meals (if comfortable) can stimulate digestion and further prevent discomfort.
Micronutrient Deficiencies on GLP-1 Inhibitors
Individuals taking GLP-1 inhibitors may be at risk for certain micronutrient deficiencies, primarily due to reduced appetite leading to lower food intake. While eating less in general can reduce many key nutrients, some important micronutrients to be mindful of include:
- Vitamin B12 and other B vitamins
- Iron
- Calcium
- Vitamin D
- Fibre
Working with a dietitian can help ensure you’re meeting these nutrient needs while navigating appetite changes. A dietitian can identify potential gaps in key nutrients and provide personalized food and supplement recommendations to support overall health.
In Summary
If you’re planning to take a GLP-1 inhibitor, we believe all patients should see a dietitian. Not only do our macronutrients (protein, fat, and carbohydrates) matter, but also our micronutrients. These can be quite hard to meet without expert support. A dietitian can help you create a sustainable eating plan to minimize symptoms while ensuring you meet your energy and nutrient requirements.
Additionally, if delayed gastric emptying is affecting your overall nutrition and quality of life while taking a GLP-1 inhibitor, discussing the long-term implications of this with your doctor is an important step. Overall, these medications aren’t a good fit for everyone – and that’s not a failure on your part!
Categorized: Gut Health & IBS
