Mounjaro Side Effects (And How To Manage Them)

Mounjaro contains the active ingredient tirzepatide. This mimics both GIP and GLP-1 hormones, which help control insulin secretion, regulate appetite and slow gastric emptying. As a result the most common Mounjaro side effects are gastrointestinal.

Mounjaro has the effect of suppressing the appetite, so there can also be side effects related to reduced calorie consumption such as fatigue, low energy, headaches and dizziness.

There can also sometimes be soreness or a reaction around the injection area.

Nausea is a Mounjaro side effect that some patients experience, especially when starting treatment. This typically lessens over time.

Some Mounjaro patients use the following techniques to help reduce their nausea:

• try eating smaller, more frequent meals
• steer clear of rich or fatty foods
• drink clear or cold beverages
• avoid trigger foods and smells
• try foods containing ginger
• antiemetics (anti-nausea medicine) such as Ondansetron or Buccastem

Diarrhoea is another common side effect of Mounjaro.

Some Mounjaro patients use the following techniques to help reduce their diarrhoea:

• stay well-hydrated
• eat bland foods (bananas, rice, applesauce, toast etc)
• over-the-counter anti-diarrhoeal medications may also be used if necessary, after speaking with your pharmacist.

If you do suffer from diarrhoea remember that it’s important to drink plenty of water to re-hydrate. You may also wish to consider oral rehydration sachets such as Dioralyte, or Loperamide capsules to slow down bowel movements.

If you experience constipation as a Mounjaro side effect, you can consider the following approaches:

• increase your intake of dietary fibre
• drink plenty of water
• engage in regular physical activity
• over-the-counter laxatives or stool softeners such as Lactulose or Senna can be used if needed in the short term.

If you experience Bloating:

• Avoid trigger foods
• Try the low FODMAP diet 
• Eat slowly and try smaller meals
• Sit up straight after meals
• Take a stroll after eating

 

Here are some ideas for how to alleviate indigestion as a side effect while taking Mounjaro:

• Avoid trigger foods
• Eat slowly and try smaller meals
• Sit up straight after meals
• Take a stroll after eating

Vomiting can occur as your body adjusts to Mounjaro.

To reduce the risk, patients and clinicians generally suggest the following:

• eat smaller meals
• avoid lying down immediately after eating.
• if vomiting persists, consult your doctor.

Here are some ideas for how to alleviate indigestion as a side effect while taking Mounjaro:

• Avoid trigger foods
• Eat slowly and try smaller meals
• Sit up straight after meals
• Take a stroll after eating

If you experience flatulence while taking Mounjaro you might want to consider the following:

• Try the low FODMAP diet 
• Eat slowly and try smaller meals
• Sit up straight after meals
• Avoid trigger foods

Some patients experience tiredness and fatigue when taking Mounjaro. This can be caused by a lack of hydration or a lack of calories (due to appetite suppression) rather than being a “direct” side effect of Mounjaro. Some patients who experience this have found the following techniques to be helpful:

• Drink plenty of fluids during the day
• Ensure you have enough calories throughout the day. Calculate your basal metabolic rate (BMR) which is the number of calories required by your body on a daily basis. From this number, aim to have a 200-300calorie deficit. 

Some patients experience headaches as a side effect of Mounjaro. To combat this, some patients have found it beneficial to:

• drink plenty of water
• get sufficient rest
• use over-the-counter pain relievers like paracetamol or ibuprofen

Some patients experience dizziness when taking Mounjaro.

Similar to fatigue, this can be caused by a lack of hydration and/or a lack of calories.

To manage this, some patients find that dizziness can be reduced by:

• Drinking plenty of fluids during the day
• Ensuring you have enough calories throughout the day. Calculate your basal metabolic rate (BMR) which is the number of calories required by your body on a daily basis. From this number, aim to have a 200-300calorie deficit. 

Skin reactions around the injection site are a common side effect:

• Use a new needle every time you inject.
• Try not use the same injection site twice in a row. You can do this by rotating injection sites:
  • Either thigh
  • Either side of belly button
  • Either arm
• You can use the following for skin irritation symptoms:
  • Hydrocortisone cream (dampens down inflammation) 
  • Chlorphenamine tablets (helps with itch) 
  • Fucidin cream (for mild bacterial infections)

Look out for symptoms of skin infection (eg cellulitis) and speak with your GP or call 111 if you are in doubt.

• Allergic reactions. Rarely, some people might experience an allergic reaction to Mounjaro. Symptoms can include itching, rash, difficulty breathing, and swelling of the face, lips, or tongue. Seek medical attention immediately if you experience these symptoms. Treatment typically involves antihistamines and corticosteroids, and severe cases may require emergency intervention.
• Pancreatitis. Symptoms of pancreatitis (inflammation of the pancreas) include severe abdominal and/or back pain, nausea, and vomiting. If you experience these symptoms, stop taking Mounjaro and seek immediate medical attention. Treatment may involve hospitalisation and supportive care.
• Gastroparesis. Where the stomach stops moving food into the bowel symptoms include nausea, vomiting, a feeling of constant fullness and reduced bowel movements, eventually leading to abdominal pain. If you have any of these symptoms, stop taking the medication and discuss with a doctor as soon as possible.
• Bowel obstruction. Where the bowel is blocked, patients will feel severe, often “griping” abdominal pain and will stop passing stools (poo) and air (wind). This can lead to life-threatening consequences such as bowel perforation, so patients with these symptoms should seek emergency medical attention.

Kidney complications. In rare cases, Mounjaro may lead to kidney problems. Symptoms include changes in urination, swelling in the legs or ankles, and persistent fatigue. If you notice these symptoms, contact your healthcare provider immediately. Management may involve adjusting your medication and regular monitoring of kidney function.

Thyroid tumours. Although uncommon, some studies suggest a potential link between GIP and GLP-1 receptor agonists and thyroid tumours. Signs include a lump in the neck, difficulty swallowing, and hoarseness. If you observe these symptoms, consult your doctor for further evaluation.

Gastrointestinal side effects are among the most frequently reported with long-term Mounjaro use. Patients often experience nausea, vomiting, diarrhoea, constipation, and abdominal pain. These symptoms tend to be most severe when starting the medication but usually subside over time. However, for some individuals, they can persist and impact daily life. Effective management of these symptoms is crucial to ensure adherence to the treatment regimen.

Although rare, there’s a risk of pancreatitis with the use of tirzepatide. Symptoms of pancreatitis include severe abdominal and/or back pain, nausea, and vomiting. If pancreatitis is suspected, Mounjaro should be discontinued immediately, and prompt medical attention is necessary. Individuals with a history of pancreatitis should discuss the associated risks with their healthcare provider before starting the medication.

Like other GLP-1 receptor agonists, Mounjaro has been linked to an increased risk of gallbladder disease, including gallstones and cholecystitis. Rapid weight loss associated with the medication can further heighten this risk. Monitor liver function and look out for symptoms of gallbladder issues, such as severe abdominal pain, nausea and jaundice.

Animal studies have indicated a potential risk of thyroid C-cell tumours with prolonged use of GLP-1 receptor agonists, including tirzepatide. Although this risk has not been confirmed in humans, those with a personal or family history of medullary thyroid carcinoma or multiple endocrine neoplasia syndrome type 2 are generally advised against using Mounjaro. Regular thyroid function monitoring is recommended for long-term Mounjaro users.

The use of Mounjaro can increase the risk of hypoglycemia, particularly when combined with other diabetes medications such as insulin or sulfonylureas. Symptoms of hypoglycemia include dizziness, sweating, confusion, and palpitations. It is essential to closely monitor blood glucose levels and adjust concurrent diabetes medications to minimise this risk. It is important to be under medical supervision, and monitor glucose levels, if glucose-lowering medication has been stopped, or replaced by, Mounjaro.

Reports of adverse effects on kidney function have been noted with GLP-1 receptor agonists, particularly in patients with pre-existing kidney conditions. If you experience symptoms such as changes in urine output, swelling in the legs or feet, and fatigue then contact your GP and/or tirzepatide provider immediately.

Significant weight loss can change how individuals view themselves and interact socially, which might lead to the need for psychological support. Moreover, the necessity for regular injections can cause anxiety or stress for some individuals.

Prolonged use of Mounjaro may affect the body’s ability to absorb certain nutrients, possibly resulting in deficiencies. Maintaining a well-balanced diet and considering supplements, as advised by a healthcare professional, can help alleviate these potential issues.

Mounjaro can interact with other medications, potentially affecting their effectiveness or increasing the risk of side effects.

• Diabetes medications. Using Mounjaro alongside insulin or other oral diabetes drugs may elevate the risk of hypoglycaemia (low blood sugar). Your doctor might need to modify the dosages of these medications to prevent low blood sugar episodes.
• Hypertension medications. Mounjaro can potentially interfere with blood pressure medications. This may require close monitoring of your blood pressure and adjustments in your medication dosages to ensure optimal control.
• Anticoagulants. There could be interactions between Mounjaro and anticoagulant medications like warfarin. Increased blood testing may be necessary to monitor your blood’s clotting ability and to adjust your anticoagulant dosage if needed.

Certain foods and supplements can also affect how Mounjaro works.

• High-fat foods. Eating meals high in fat can worsen gastrointestinal side effects associated with Mounjaro. To minimise these effects, try to stick to a balanced diet that includes moderate amounts of fat.
• Vitamins and minerals. While Mounjaro does not notably impact the absorption of vitamins, it is still crucial to maintain a well-balanced diet rich in essential vitamins and minerals to ensure overall health.

Specific medical conditions may influence how effectively Mounjaro works or elevate the risk of adverse effects.

• Gastroparesis. Those with delayed gastric emptying should use Mounjaro cautiously, as it can potentially aggravate this condition.
• Pancreatitis history. If you have a history of pancreatitis, it’s essential to discuss this with your healthcare provider before starting Mounjaro, as the medication could increase the likelihood of recurrence.
• Thyroid cancer history. Individuals with a personal or family history of thyroid carcinoma should avoid using Mounjaro due to the potential risk of developing thyroid tumours.

Following certain precautions can help ensure the safe and effective use of Mounjaro.

• Regular check-ups. Scheduling consistent appointments with your healthcare provider is essential. These visits allow your doctor to monitor your progress and make any necessary adjustments to your treatment. Routine blood tests and other evaluations can help track your overall health and how well you’re responding to the medication.
• Staying hydrated. Adequate hydration is crucial for managing side effects like nausea and constipation. Aim to drink at least 8 glasses of water each day to stay properly hydrated.
• Balanced diet. Adhering to a well-rounded diet is important for your overall health and can help minimise gastrointestinal side effects. Ensure your meals include a variety of nutrients and moderate fat content.

Exceeding the prescribed dosage of Mounjaro will not increase its effectiveness and may lead to severe side effects. If you suspect that you have taken too much, seek medical attention immediately. Symptoms of an overdose can include severe nausea, vomiting, and hypoglycemia (low blood sugar). Treatment will focus on relieving these symptoms and may involve supportive care and monitoring.

This article is for general information only and should not be used for the diagnosis or treatment of medical conditions. Medic Spot Limited has used all reasonable care in compiling the information but makes no warranty as to its accuracy. Consult a doctor or other health care professional for diagnosis and treatment of medical conditions. In the event of an emergency, please call 999 for immediate assistance.

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