Medications
Mounjaro Side Effects: What to Expect and How to Manage Them
Learn about common Mounjaro side effects like nausea and diarrhoea, plus practical strategies to manage them effectively.
Well Revolution
February 5, 2026
Understanding the potential side effects of Mounjaro (tirzepatide) is an important part of making an informed decision about weight loss treatment. While most people tolerate the medication well, knowing what to expect and how to manage common issues can make your experience much smoother.
Common Side Effects
The most frequently reported side effects of Mounjaro are gastrointestinal in nature. In clinical trials, the following were observed:
- Nausea: Approximately 18% of patients
- Diarrhoea: Approximately 17% of patients
- Decreased appetite: Approximately 11% of patients
- Vomiting: Approximately 9% of patients
- Constipation: Approximately 7% of patients
- Abdominal pain: Approximately 6% of patients
- Indigestion: Approximately 5% of patients
Important Context
These side effects are typically:
- Dose-dependent: More common at higher doses
- Most pronounced during titration: When your dose is increasing
- Temporary: Usually resolve within 4-8 weeks as your body adjusts
- Mild to moderate: Rarely severe enough to stop treatment
Managing Nausea and GI Symptoms
Most gastrointestinal side effects can be managed effectively with simple strategies:
Eat Smaller, More Frequent Meals
Large meals can overwhelm your digestive system while on Mounjaro. Try eating 4-5 smaller meals rather than 2-3 large ones.
Avoid Fatty, Greasy, or Spicy Foods
These foods are harder to digest and more likely to trigger nausea. Focus on bland, easily digestible foods during the first few weeks at each new dose.
Eat Slowly and Stop When Satisfied
Mounjaro helps you feel full faster. Pay attention to your body's signals and stop eating before you feel stuffed.
Stay Hydrated
Drink plenty of water throughout the day. If you experience vomiting or diarrhoea, replace lost fluids and electrolytes.
Time Your Injection Strategically
Some people find that injecting in the evening (so they sleep through the initial hours after injection) helps manage symptoms.
Sulfur Burps: A Common Complaint
Many people on GLP-1 medications report experiencing sulfur burps (burps with a rotten egg smell). While not dangerous, they can be unpleasant. To minimise them:
- Avoid carbonated drinks
- Limit high-sulfur foods like eggs, cruciferous vegetables, and garlic
- Eat slowly to reduce swallowed air
- Consider over-the-counter antacids or simethicone if persistent
Serious Side Effects
While rare, some serious side effects require immediate medical attention:
Pancreatitis
Symptoms include severe abdominal pain that may radiate to your back, nausea, and vomiting. Stop taking Mounjaro and seek medical help immediately if you experience these symptoms.
Gallbladder Problems
Rapid weight loss can increase the risk of gallstones. Watch for pain in your upper right abdomen, especially after eating fatty foods.
Severe Allergic Reactions
Seek immediate medical help if you experience swelling of the face, lips, or throat, difficulty breathing, or severe rash.
Kidney Problems
If you experience decreased urination or swelling in your legs or feet, contact your doctor.
Hypoglycaemia (Low Blood Sugar)
This is more common in people also taking insulin or sulfonylureas for diabetes. Symptoms include shakiness, sweating, confusion, and rapid heartbeat.
Boxed Warning: Thyroid Tumours
Mounjaro carries a boxed warning about thyroid C-cell tumours based on studies in rodents. While this has not been confirmed in humans, you should not take Mounjaro if you have:
- A personal or family history of medullary thyroid carcinoma (MTC)
- Multiple Endocrine Neoplasia syndrome type 2 (MEN 2)
When to Contact Your Doctor
Reach out to your prescriber if you experience:
- Side effects that don't improve after several weeks
- Severe or persistent vomiting (risk of dehydration)
- Signs of pancreatitis or gallbladder problems
- Any symptoms that concern you
Side Effects Compared to Wegovy
If you're wondering whether Mounjaro has more side effects than Wegovy, the answer is no. Clinical trials show no significant difference in the frequency or severity of side effects between tirzepatide and semaglutide. Both medications affect the same GLP-1 pathway, so their side effect profiles are very similar.
Support Throughout Your Treatment
At Well Revolution, our care team is available seven days a week to help you manage any side effects and make adjustments to your treatment plan as needed. We provide ongoing support to help you get the best results from your weight loss medication.
References
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