The most common GLP-1 side effects are nausea, diarrhea, vomiting, constipation and stomach discomfort. They are usually mild and improve as your body adjusts. Seek care promptly for severe or persistent stomach pain, signs of dehydration, or symptoms of an allergic reaction.
Common side effects
These affect many people, especially in the first weeks and after each dose increase:
- Nausea and feeling full quickly
- Diarrhea or constipation
- Vomiting
- Stomach pain, bloating, burping or heartburn
- Fatigue, headache or dizziness
- Mild reactions at the injection site
Tips that often help
- Eat smaller meals and stop when you feel full.
- Limit greasy, fried and very sweet foods.
- Drink fluids steadily through the day.
- Eat slowly and avoid lying down right after meals.
- Do not increase your dose faster than prescribed. Tell your clinician if side effects are hard to manage; a slower dose increase may help.
When to call your doctor or seek urgent care
Contact your clinician promptly, or seek urgent care, if you have:
- Severe stomach pain that does not go away, with or without vomiting, which can be a sign of pancreatitis
- Pain in the upper right abdomen, fever, yellowing of the skin or eyes, or clay-colored stools, which can signal gallbladder problems
- Signs of dehydration such as very little urine, dizziness or extreme thirst after repeated vomiting or diarrhea; dehydration can harm the kidneys
- Low blood sugar symptoms (shakiness, sweating, confusion), especially if you also take insulin or a sulfonylurea
- A lump or swelling in the neck, trouble swallowing or persistent hoarseness
- Changes in vision if you have diabetes
- Severe constipation with bloating and inability to pass gas
Call 911 for swelling of the face, lips or throat, trouble breathing, or severe dizziness, which can be signs of a serious allergic reaction.
Before surgery or a procedure
GLP-1 medications slow stomach emptying. Tell every surgeon, anesthesiologist and endoscopy team that you take one, as they may give you special instructions before sedation.
Who should not take GLP-1 medications
They should not be used by people with a personal or family history of medullary thyroid carcinoma or multiple endocrine neoplasia syndrome type 2, or by people who are pregnant. Tell your clinician about any history of pancreatitis, gallbladder disease, kidney disease or diabetic eye disease.
How Voss Family Clinic supports you
Patients in our medical weight loss program have scheduled follow-up visits to review side effects and adjust the dose. If you have a question between visits, call our office at (281) 617-8671 during business hours. Comparing medications? Read Ozempic vs Wegovy vs Zepbound vs Mounjaro.
Frequently asked questions
How long do GLP-1 side effects last?
Stomach side effects are usually worst in the first few weeks and after dose increases, and ease for most people over time.
Does hair loss happen on GLP-1s?
Some people notice hair shedding during rapid weight loss. It is usually temporary. Mention it to your clinician, especially if it is significant.
Should I stop the medication if I feel sick?
Do not stop or skip doses on your own for mild symptoms; call your clinician first. For severe symptoms listed above, seek care right away.
Considering medical weight loss? Request a consultation in Sugar Land.
Medical Disclaimer: The information in this article is provided for general educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Consult a qualified healthcare professional regarding your individual health concerns. If you are experiencing a medical emergency, call 911 or seek emergency medical care.
Sources
- FDA prescribing information and Medication Guides for Ozempic, Wegovy, Mounjaro and Zepbound
- American Society of Anesthesiologists: guidance on GLP-1 receptor agonists before procedures