Navigating GLP-1 Side Effects? We Asked Experts What Actually Helps

As a dietitian who spent almost five years of my career working with people taking GLP-1s, I have extensive experience helping people manage their side effects. Most of the side effects I saw in practice were related to digestion and included nausea, vomiting, diarrhea, constipation, along with low energy levels and brain fog (primarily driven by inadequate dietary intake).

But while I have a lot of experience with GLP-1 side effects from a dietitian's perspective, I also spoke with George W. Carroll, MD, Co-Founder & Chief Medical Director, GLPrelief, located in Maitland, FL, to get a physician's take on why side effects of GLP-1s are so common, how long they last, and when it's time to speak with your doctor.

This article will blend the clinical experiences of both Dr. Carroll and myself to provide a list of helpful strategies, products, and services for managing GLP-1 side effects so you can stay consistent with your medication plan and work toward your health goals.

Low appetite is par for the course on GLP-1s, but fortunately, there are lots of strategies you can use to ensure you get the nutrients you need while dealing with low appetite.

• Eat smaller, more frequent meals. Since you feel full quickly on GLP-1s, eating large meals can quickly become uncomfortable. Instead, aim for four to six "mini meals" that include a source of protein spread evenly throughout the day.
• Eat on a schedule: Instead of relying on hunger signals (which often diminish significantly on GLP-1s), set alarms to eat every 3 to 4 hours.
• Eat protein first: Getting enough protein is crucial to preventing muscle loss during weight loss. To make sure you get enough, eat your protein first (before you get too full).
• Enjoy smoothies: Liquids are often easier to tolerate when you're nauseous or have a poor appetite, so smoothies with a source of protein can be a great way to manage it.

According to Carroll, most GLP-1 side effects stem from the medication slowing stomach emptying and suppressing appetite for far longer than the body's own GLP-1 normally does. "GLP-1 medications are engineered to mimic glucagon-like peptide-1," he explains, "a hormone the gut naturally releases after a meal." However, while the version produced by the body peaks and clears within minutes, the medication version keeps that signal active for days, he adds.

The result? "Food sitting longer, the brain's nausea centers staying on alert longer, and a digestive rhythm patients have lived with for decades suddenly running on a different clock," says Carroll. It's this "mismatch" that people taking GLP-1 medications often feel in the first few weeks, and Carroll notes that it's the root of many of the most common symptoms of GLP-1s, like nausea and feeling full after only a few bites.

Carroll says that in his practice, the most common side effects of GLP-1 medications he sees in his patients are nausea, digestive discomfort, fatigue, brain fog, and muscle cramping, which often worsen when appetite drops and hydration, electrolytes, and protein intake decline.

However, with the exception of nausea, Carroll explains that what often tips a patient towards wanting to discontinue the medication usually isn't one severe symptom. Rather, "it's the accumulation of small ones at a moment when they don't know whether what they're feeling is normal." That's why it's critical to speak with your doctor if you're experiencing side effects, even if they don't feel severe enough to mention. 

While most people are dealing with daily discomfort rather than emergencies, Carroll says that there are some serious complications worth knowing about, including acute pancreatitis, gallbladder disease, and severe dehydration from prolonged vomiting or diarrhea. If you have abdominal pain that lasts for more than a few hours, Carroll recommends notifying your doctor immediately, as this could be an early sign of pancreatitis or gallbladder disease.

Carroll stresses that while these complications are rare, they're the reason GLP-1 medications require clinician oversight rather than self-administration. He adds that these complications are also a key reminder that prolonged, unmanaged GI symptoms aren't just uncomfortable. "Left alone for too long, they can become the upstream cause of complications that send people to the emergency room."