How to anticipate and tackle GLP-1 medication side effects

Key Points:

1. GLP-1 agonist medications mimic hormones in the body that slow digestion—which can trigger nausea, vomiting and other digestive issues.
2. To help your body adjust to the effects on digestion, your provider will probably start you on a low dose of GLP-1 medication and gradually increase the dose. Staying hydrated and eating fiber-rich foods can also discourage gastrointestinal discomfort. 
3. If you have severe nausea that doesn’t stop, request a callback from a provider. They may prescribe an anti-nausea medication to help.

GLP-1 medications help many of us eat less to reduce our body weight. When we pair them with diet and exercise, we can improve many cardiovascular and immune health conditions, too!

But because GLP-1s have a powerful effect on digestion, they can cause some curious side effects—Especially in the early days of treatment.

If you’re just starting Shed It and want to get a feel for the potential side effects ahead, read on.

Here, we’ll cover common concerns and side effects to watch out for. Then, share some adjustments that can help you feel your best.

How GLP-1 medications work

Semaglutide is the active ingredient in compounded Semaglutide, Ozempic®* and Wegovy®*. Tirzepatide is the active ingredient in Zepbound®* and Mounjaro®*. Liraglutide is the active ingredient in Sexenda®* and Victoza®*.

These medications are GLP-1 receptor agonists. That means they act like the glucagon-like peptide 1 hormone naturally made in our bodies.

When we eat, our digestive tract releases GLP-1. It slows the rate food leaves our stomach—a process called gastric emptying. It encourages the production of insulin, which helps lower blood sugar levels. And it sends messages to our brain that we’re getting full.

GLP-1 medications do this over a long period—much longer than the GLP-1 made in our body does naturally. So we feel fuller longer, less hungry overall, have slower digestion, and our blood sugar levels stay low.

Tirzepatide medications also mimic the glucose-dependent insulinotropic polypeptide (GIP) hormone. So they may also reduce inflammation and boost metabolism.

Together, these factors help some people eat less and lose weight—but they can sometimes cause uncomfortable side effects while they do so.

Common GLP-1 side effects

How long GLP-1 side effects last differs by person. But most people on GLP-1s experience mild side effects that go away when their body adjusts to their medication.

During every Shed It follow-up consultation, we’ll check how you’re feeling on your current medication and dosage. If you’re struggling with side effects, let your provider know—they may lower your dose or adjust your treatment plan to help you feel more comfortable.

Mild GLP-1 side effects include:

• Stomach pain
• Nausea
• Vomiting
• Diarrhea
• Constipation
• Headache
• Heartburn/acid reflux
• Gassiness/burping
• Bloating
• Tiredness or fatigue
• Dizziness

People with a medical history of gastrointestinal, eye and specific thyroid conditions are at most risk for severe GLP-1 side effects. (Learn more about safety and risks in this Dr. B article.) But it’s vital to report any new or worsening symptoms to your provider.

Get help right away if you experience:

• Signs of an allergic reaction (rash, shortness of breath, itching/swelling, problems swallowing, swelling in the mouth or tongue)
• Blood in urine or changes in the amount you pee (which could signal a kidney issue)
• Vision changes like decreased or blurred vision
• A fast heartbeat
• Mental or mood changes, like depression or suicidal thoughts
• Signs of low blood sugar (shaking, dizziness, sweating, fast heartbeat, confusion or blurred vision)
• Severe stomach pain or vomiting that doesn’t stop
• Yellowing of the eyes or skin
• Lumps in the neck or jaw

How to treat mild side effects

Getting lots of sleep, drinking plenty of water, eating a balanced diet and staying physically active can also help minimize side effects.

Adjust your eating habits

• Nausea, vomiting, stomach pain: Eat smaller portions. Food stays in your stomach longer now, so there’s less room in it! Try eating snacks to lighten the digestive load.
• Constipation: Drink more water and add fiber-rich foods (like fruits and vegetables) to your meal plans. Physical activity can also help, so try moving around after meals.
• Heartburn or acid reflux: Avoid high-fat and ultra-processed foods, which need a lot of stomach acid to break down. With more time digesting in the stomach, the acid can back into the esophagus and cause pain!
• Tiredness or dizziness: Keeping blood sugar levels steady can help with energy. So eat regular small snacks of energizing high-fiber foods throughout the day. 
• Headaches: Drinking plenty of water and managing nausea might help ease those symptoms. If you feel dizzy or confused, you could be experiencing low blood sugar—so seek medical help if necessary.

Try over-the-counter medicines

• Famotidine (Pepcid) reduces stomach acid. For heartburn, take 20 or 40 mg 2 times per day for up to 12 weeks. 
• Docusate (Colace) is a stool softener. For constipation, take 100 mg 2 times a day as needed. 
• Miralax is a laxative. For constipation, take 1 packet or capful daily as needed. 

Request a callback for prescription relief

If you have severe nausea that won’t go away, request a callback from your patient dashboard. A nurse or online weight loss doctor may prescribe an anti-nausea medicine to help.

The consultation is included in your monthly program fee. Your provider will send the prescription to your pharmacy of choice. You can use insurance to pay for the prescription. If you have to pay for it out-of-pocket, Dr. B will help you find the lowest prescription cost in your area and email you a drug discount card to secure that price!

*Wegovy®, Ozempic®, Zepbound®, Mounjaro®, Sexenda® and Victoza® are registered trademarks of their respective owners. Our use of these names is for informational purposes only and does not imply any affiliation, endorsement or approval by the trademark holders.

Sources: 

Farzam, K., Patel, P. (2024). Tirzepatide. StatPearls Publishing.

Gorgojo-Martínez, J.J., et al. (2022). Clinical recommendations to manage gastrointestinal adverse events in patients treated with GLP-1 receptor agonists: A multidisciplinary expert consensus. Journal of Clinical Medicine.

Lilly. Zebound Clinical Data.

Ryan, D. H., et al. (2024). Long-term weight loss effects of semaglutide in obesity without diabetes in the SELECT trial. Nature Medicine.

Sodhi, M., et al. (2023). Risk of gastrointestinal adverse events associated with glucagon-like peptide-1 receptor agonists for weight loss. Journal of the American Medical Association Network.