Mounjaro side effects

Mounjaro, or tirzepatide, is a cutting-edge weight loss medication that reduces your appetite and slows down how quickly your stomach empties, making it easier to stick to a low-calorie diet. In the SURMOUNT 1 trials, participants using the highest dose of 15mg lost up to an impressive 22.5% of their starting body weight over 72 weeks. While it sounds like a dream come true, it’s important to understand the potential side effects before starting Mounjaro. In this blog, we’ll review Mounjaro’s side effects and what you can do to reduce them.

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Mounjaro side effect key takeaways

Mounjaro (tirzepatide) is a powerful weight loss medication, but like any treatment, it comes with a list of potential side effects. The SURMOUNT 1 trial, which studied the effects of Mounjaro, revealed the 10 most common side effects experienced by participants. Here’s a breakdown in simple terms:

The 10 most common side effects of Mounjaro

1. Nausea – Feeling queasy or sick to your stomach was the most common side effect.
2. Diarrhoea – Loose or watery stools were also frequently reported.
3. Constipation – Some participants experienced difficulty in bowel movements.
4. Indigestion (Dyspepsia) – A feeling of discomfort or pain in the upper belly.
5. Vomiting – Some people reported throwing up as a side effect.
6. Headache – Mild to moderate headaches were noted.
7. Abdominal pain – Stomach aches or cramps were reported by some users.
8. Hair loss (Alopecia) – A small percentage of participants noticed hair thinning or loss.
9. Dizziness – Feeling lightheaded or unsteady was another side effect.
10. Burping (Eructation) – An increase in burping was observed in some participants.

Side effect percentages from the SURMOUNT 1 trial

The table below shows how common these side effects were at different doses of Mounjaro compared to a placebo (a substance with no active medication) [1].

Table of side effects experienced by participants of the SURMOUNT-1 trial

If you’re considering Mounjaro, it’s important to weigh the benefits against the risks. While many people have seen life-changing weight loss results, side effects like nausea and diarrhoea are pretty common, especially at higher doses. Always consult a healthcare professional to see if Mounjaro is right for you.

What is Mounjaro?

Mounjaro, manufactured by Eli Lilly, is a weight-loss injection that uses an active ingredient called tirzepatide.

This medication is unique because it combines two special hormones, GLP-1 (Glucagon-Like Peptide-1) and GIP (Glucose-Dependent Insulinotropic Polypeptide). These hormones are naturally found in your body and are known as incretins, which help manage blood sugar levels and influence weight.

By combining GLP-1 and GIP, Mounjaro is nicknamed a “twincretin.” These hormones work together to help with weight loss in three key ways:

• Reducing your appetite so you feel less hungry [2], [3].
• Making you feel full longer [2], [3].
• Slowing down how quickly your stomach empties food [4].

Scientists first noticed the powerful effects of combining GLP-1 and GIP in early tests on mice with obesity caused by diet [5]. The results showed much greater weight loss than using either hormone alone. Seeing its potential, Eli Lilly patented tirzepatide in 2016 [6] and later proved its effectiveness in humans through the SURMOUNT clinical trials.

The following table summarises how the two incretins, GLP and GIP, work to promote weight loss.

How effective is Mounjaro?

Before discussing Mounjaro’s side effects, let’s first discuss its effectiveness for weight loss.

Mounjaro (tirzepatide) has gained attention for its incredible results, especially during the SURMOUNT 1 trial [1].

This clinical study focused on how well Mounjaro helped people without diabetes lose weight, specifically those who were either obese or overweight.

Participants in the trial had:

• A body mass index (BMI) of 30 or higher, or
• A BMI of 27 or higher along with a weight-related condition like high blood pressure.

Over 72 weeks, those who took the highest dose of Mounjaro 15mg, lost an average of 22.5% of their body weight, with nearly 90% of participants achieving at least 5% weight loss [1].

To put this into perspective, another popular weight-loss medication, semaglutide, leads to an average weight loss of 12.4% [7].

Mounjaro’s ability to deliver superior weight loss results is due to its unique combination of two hormones, GLP-1 and GIP, which work together to reduce appetite, increase feelings of fullness, and slow digestion.

This combination makes it more effective than many other weight loss medications on the market.

What weight loss results can you expect when starting Mounjaro?

To get a rough idea of how much weight you can lose when starting Mounjaro, look at the results from the SURMOUNT 1 trial.

The SURMOUNT 1 trial: how Mounjaro helps with weight loss

The SURMOUNT 1 trial was a groundbreaking study examining how effective Mounjaro (tirzepatide) is for weight loss  [1].

It involved 2539 adults with a body-mass index (BMI) of 30 or more, or 27 or more with at least one weight-related health issue (like high blood pressure), but none of the participants had diabetes. The participants were split into four groups and given weekly injections for 72 weeks  [1]:

• Tirzepatide 5mg (Mounjaro 5mg)
• Tirzepatide 10mg (Mounjaro 10mg)
• Tirzepatide 15mg (Mounjaro 15mg)
• Placebo (no active medication)

The trial included a 20-week period where the doses were gradually increased. The results showed significant weight loss for those using Mounjaro compared to the placebo group  [1]. Let’s take a closer look.

Weight loss results with Mounjaro over 72 weeks

Here’s a breakdown of how much weight participants lost on average during the trial:

What about the side effects from the SURMOUNT 1 trial?

While the SURMOUNT 1 trial demonstrated that Mounjaro delivered incredible weight loss results, the trial also revealed some side effects. These included nausea, diarrhoea, constipation, and indigestion, which were more common during the early stages of treatment. Most side effects were mild and temporary, improving as the body adjusted to the medication [8].

Now, let’s study the side effects of Mounjaro in more detail.

Side effects of Mounjaro

Mounjaro (tirzepatide) is a powerful medication used for weight loss, but like all medicines, it can come with some side effects. The patient information leaflet for Mounjaro lists several common and widespread side effects [9]. Let’s break them down in simple terms.

Low blood sugar (hypoglycaemia) and Mounjaro

While Mounjaro is designed to help regulate blood sugar levels, it can sometimes cause low blood sugar, especially if you’re also taking other diabetes medications like insulin or sulphonylureas. This happens because the combination can lower your blood sugar too much.

If you’re using Mounjaro along with insulin or sulphonylureas, your doctor might need to adjust the doses of these medications to prevent low blood sugar. The patient information leaflet lists this side effect as very common or common [9].

Symptoms of low blood sugar

Knowing the signs of low blood sugar is important so you can act quickly. Symptoms include:

• Headaches
• Feeling weak or drowsy
• Dizziness
• Feeling extra hungry
• Confusion or irritability
• Fast heartbeat or sweating

If you notice these symptoms, treat them immediately by consuming something sugary, like a drink or snack. Make sure to regularly monitor your blood sugar levels and consult your doctor if you’re unsure how to manage them.

Very common side effects of Mounjaro

The term “very common” means these side effects may affect more than 1 in 10 people. These include:

• Nausea
• Vomiting
• Diarrhoea
• Constipation

These side effects are usually mild and tend to occur when you first start Mounjaro, especially during the dose escalation period when your body adjusts to the medication.

This is why there is a gradual dose escalation to allow your body to adjust to Mounjaro’s effects. So, don’t try to jump to higher doses straight away; doing so will cause these side effects to be more severe.

These effects usually improve over time. However, if they become severe, speak to your doctor immediately. At Courier Pharmacy, our weight loss programme includes free ongoing support from our team of prescribers, so you are never left on your own. If you are having difficulties with your side effects and are unsure if you should increase your dose, our prescribers are always available to help guide you to get the most out of your medication.

Managing very common side effects of Mounjaro

Using Mounjaro (tirzepatide) for weight loss can sometimes cause nausea and vomiting, often referred to as “Mounjaro sickness.” These side effects are considered very common, but the good news is there are simple ways to manage them.

Mounjaro-related nausea and vomiting

If you’re feeling sick while using Mounjaro, here are some tips to help you feel better:

• Sip small amounts of water or electrolyte drinks often to stay hydrated.
• Eat small, plain meals—stick to simple foods and avoid spicy dishes like curries.
• Avoid greasy, rich, or fatty foods, so no full English breakfasts for now!
• Stay away from caffeine, sugary drinks, or alcohol—they can make nausea worse.
• If you smoke, try to avoid it, especially on an empty stomach.
• Get some fresh air—it can help settle your stomach.
• Rest when you feel tired, but also try distraction techniques like watching TV, reading, or going for a walk to distract yourself from the nausea.
• Talk to your pharmacist or doctor about over-the-counter or prescription anti-sickness medications, such as domperidone or ondansetron.
• Take your Mounjaro dose with food, as this might reduce nausea.
• Slowly reintroduce foods into your diet, giving your stomach time to adjust.

Watch out for dehydration

Frequent vomiting can lead to dehydration, which can make you feel even worse. Signs of dehydration include:

• Feeling very thirsty
• Having a dry mouth or lips
• Dark yellow urine or not needing to pee as often
• Feeling dizzy or lightheaded

If you think you’re dehydrated or can’t stop vomiting, speak to your doctor right away. They can help you manage the symptoms and adjust your treatment if needed.

What you should know

Mounjaro-related nausea and vomiting are usually temporary and tend to improve as your body gets used to the medication. Following these tips can help ease the symptoms, but don’t hesitate to contact your doctor or pharmacist if you’re struggling.

Mounjaro-related diarrhoea

If you’re using Mounjaro (tirzepatide) and experience diarrhoea, don’t worry—it’s a common side effect that can usually be managed with a few simple steps:

• Drink plenty of fluids, like water or electrolyte drinks such as Dioralyte, to stay hydrated and replace lost electrolytes.
• Avoid spicy, fatty, or greasy foods—so hold off on that fry-up breakfast!
• Skip caffeine, as it can worsen dehydration because of its diuretic effect.
• Stay away from fruit juices and alcohol, which can upset your stomach further.
• You can use over-the-counter diarrhoea medicines like loperamide for only 1-2 days. Please don’t use them for longer than 48 hours without speaking to your doctor.
• Rest and avoid stress, as it can worsen symptoms.
• When you start feeling better, eat small amounts of plain food and slowly reintroduce other foods into your diet. Rushing back to a normal diet too quickly can upset your stomach again.

It’s important to stay hydrated, as diarrhoea can lead to dehydration. If the diarrhoea is severe, doesn’t improve, or lasts several days, contact your doctor. See the section below for signs of dehydration and how to manage it.

Mounjaro-related constipation

Constipation is another common side effect of Mounjaro. If you’re feeling backed up, don’t worry—here are some tips to help get things moving:

• Eat more fibre: Add high-fibre foods like fruits, vegetables, whole grains, and beans to your meals. These can help soften stools and make bowel movements easier.
• Stay hydrated: Drink lots of water throughout the day to keep stools soft and prevent dehydration, which can worsen constipation.
• Exercise regularly: Gentle activities like walking or stretching can help stimulate your digestive system.
• Establish a routine: Try to go to the bathroom at the same time every day, especially after meals, to train your body for regular bowel movements.
• Don’t hold it in: If you feel the urge to go, don’t delay—it can make constipation worse.
• Use stool softeners or laxatives: Over-the-counter options can help, but only use them occasionally and check with your doctor if needed.
• Eat smaller meals: Smaller, more frequent meals can help if you feel bloated or too full. Avoid large meals that can cause discomfort.
• Manage stress: Stress can impact digestion, so try relaxation techniques like deep breathing or meditation to help your digestive system.

If constipation doesn’t improve with these changes, or if you haven’t passed stool for more than three days, it’s time to consult your doctor. Severe constipation can be painful and may need prescription treatments.

In rare cases, constipation can lead to a bowel obstruction, which is a medical emergency. Call 999 immediately if you experience symptoms like severe stomach pain, bloating, cramping, vomiting, trouble passing gas, fever, or loss of appetite.

What you should know

Diarrhoea and constipation are common side effects of Mounjaro, especially during the early stages of treatment. Most people find that these symptoms improve as their bodies adjust to the medication. However, if symptoms persist or become severe, always seek advice from your healthcare provider or contact us for more advice.

Mounjaro and dehydration

Dehydration happens when your body loses more fluids than it takes in, which can cause serious problems if not dealt with quickly. If you’re using Mounjaro (tirzepatide), it’s important to watch out for dehydration, especially if you’ve experienced side effects like diarrhoea or vomiting. Spotting the signs early can help you avoid complications.

Signs of dehydration

Here are some common signs that your body might be dehydrated:

• Feeling thirsty
• Dark yellow pee or not peeing as much as usual
• A dry mouth or throat
• Feeling tired or dizzy
• Headaches
• Feeling confused or irritable

How to deal with dehydration

If you notice any signs of dehydration [10], here’s what you can do to feel better:

• Drink water regularly, even if you don’t feel thirsty.
• Try electrolyte drinks to replace important minerals your body has lost.
• Eat foods with high water content, like fruits (e.g., watermelon) and vegetables (e.g., cucumber).
• Avoid drinks that can make dehydration worse, such as alcohol or caffeinated drinks like coffee or energy drinks.
• Rest and avoid heavy exercise or strenuous activities until you’re feeling better.

What you should know

Dehydration is something you can usually manage at home by staying hydrated and making small lifestyle changes. However, if you’re still feeling unwell or your symptoms get worse, contact your doctor straight away. Severe dehydration can be dangerous and may require medical attention.

Mounjaro’s common side effects

Mounjaro (tirzepatide) is an effective weight loss medication, but like most medications, it can come with some side effects. These side effects are usually mild and temporary, but it’s important to know how to manage them if they occur. Let’s break down some of the common side effects and what you can do about them.

Here are some of the common side effects you might experience while using Mounjaro:

• Allergic reactions: This could include symptoms like a rash, itching, or eczema.
• Dizziness: Some people report feeling lightheaded during their weight management treatment.
• Low blood pressure: This can happen during treatment and might make you feel faint or dizzy.
• Abdominal pain: Some people experience discomfort or cramping in their stomach.
• Indigestion (dyspepsia): This is a feeling of discomfort or burning in your upper stomach.
• Stomach bloating: A sensation of fullness or swelling in the stomach area.
• Burping (eructation): This is the release of gas from your stomach through your mouth.
• Gas (flatulence): Excessive gas in your digestive system can cause discomfort.
• Reflux or heartburn (GERD): This happens when stomach acid moves up into your oesophagus, causing a burning sensation.
• Hair loss: Some users have reported hair thinning or loss during weight management treatment.
• Fatigue (tiredness): Feeling unusually tired or lacking energy.
• Injection site reactions: This includes redness, itching, or mild pain where the injection is given.

What you should know

Most of these side effects are mild and temporary, meaning they often go away as your body gets used to the medication. However, if any of these symptoms persist or become worse, it’s important to contact your doctor for advice. They may adjust your treatment or recommend ways to manage the side effects.

When to seek help

If you experience severe or unusual symptoms, such as intense stomach pain, difficulty breathing, or severe allergic reactions, seek medical attention immediately. Your doctor or pharmacist can provide guidance on how to handle these situations.

Mounjaro injection site reactions

If you notice redness, itching, or discomfort at the injection site, here’s how to manage it:

• Use an antihistamine (tablet or cream) like cetirizine, fexofenadine 120mg or chlorpheniramine 4mg to reduce itching.
• Rotate your injection site weekly by using different areas of your body or different spots on the same side [11].
• Clean the injection area thoroughly before injecting.
• Always use a new, straight needle for each injection.
• Use an ice pack before injecting to numb the area or after injecting to reduce swelling.

If the reaction becomes severe or doesn’t improve, consult your doctor.

Dizziness caused by Mounjaro

Dizziness is another common side effect. Here’s how you can manage it:

• Drink plenty of water to stay hydrated.
• Lie down until the dizziness passes, then get up slowly.
• Avoid driving or operating machinery if you feel dizzy.
• Get enough rest and reduce stress with relaxation techniques.
• Take your Mounjaro dose after eating or drinking, especially if dizziness occurs after your injection.

Dizziness can sometimes be linked to low blood sugar. If you also experience symptoms like headaches, weakness, or irritability, speak to your doctor to check your blood sugar levels.

Low blood pressure caused by Mounjaro

Low blood pressure (hypotension) can sometimes occur while using Mounjaro. Here’s how to manage it:

• Drink plenty of water to keep your blood pressure stable.
• Eat small, frequent meals instead of large ones.
• Get up slowly from sitting or lying down to avoid feeling lightheaded.
• Regularly check your blood pressure and discuss any significant drops with your doctor.

If symptoms like fainting, confusion, or dizziness persist, contact your doctor immediately.

Stomach pains caused by Mounjaro

Stomach pain is a common side effect and can often be managed with these tips:

• Eat a balanced diet with fruits, vegetables, and whole grains.
• Avoid greasy, spicy, or acidic foods that can irritate your stomach.
• Eat smaller meals throughout the day instead of large ones.
• Use a hot water bottle or over-the-counter painkillers (after consulting your pharmacist).
• If the pain persists, speak to your pharmacist or doctor for advice.

In rare cases, severe stomach pain could be a sign of a more serious condition like pancreatitis. If the pain is intense or doesn’t go away, contact your doctor or visit A&E.

Indigestion (dyspepsia) caused by Mounjaro

If you experience indigestion, try these steps:

• Eat smaller, more frequent meals to avoid overloading your stomach.
• Avoid spicy, greasy, and fatty foods.
• Limit alcohol and caffeine, as they can worsen indigestion.
• Eat plain foods like bananas, rice, or oatmeal.
• Stay upright for at least an hour after eating.
• Consider over-the-counter antacids or proton pump inhibitors (consult us for  a FREE consultation if you are unsure).

Stomach bloating caused by Mounjaro

Feeling bloated? Here’s how to manage it:

• Drink plenty of water to stay hydrated.
• Avoid gas-producing foods like beans, fizzy drinks, and broccoli.
• Eat smaller meals and chew your food slowly.
• Try light exercise, like walking, after meals to aid digestion.
• Consider probiotics or anti-bloating products like Wind-Eze (consult us for a FREE consultation if you are unsure).

Burping or eructation caused by Mounjaro

If burping becomes an issue, especially eggy or sulphur burbs [12] here’s what you can do:

• Eat slowly and avoid swallowing air while chewing.
• Skip fizzy drinks and chewing gum.
• Drink water between meals instead of with meals.
• Avoid overeating and high-fat foods.
• Use antacids or anti-gas medications if needed (consult your pharmacist).

Gas (flatulence) caused by Mounjaro

If you’re dealing with excess gas, try these tips:

• Avoid foods that cause gas, like onions, beans, and broccoli.
• Drink lots of water to help digestion.
• Eat smaller meals throughout the day.
• Stay active with light exercise, like walking.
• Use over-the-counter remedies like simethicone to relieve gas.

Reflux or heartburn caused by Mounjaro

Heartburn or acid reflux can sometimes occur. Here’s how to manage it:

• Avoid trigger foods like spicy dishes, citrus, and chocolate.
• Eat smaller meals to reduce pressure on your stomach.
• Stay upright for at least 30 minutes after eating.
• Sleep with your head slightly raised to prevent acid reflux.
• Avoid smoking, as this can worsen the symptoms of heartburn.
• Use over-the-counter antacids if needed (consult us for advice if you are unsure).

Managing hair loss caused by Mounjaro

Hair loss is a rare side effect but can happen [13]. Results from the SURMONT-1 trial suggest that as many as 5.71% of the participants from the trial experienced some degree of hair loss or alopecia [1]. Here’s how to manage it:

• Maintain a diet rich in vitamins like biotin, iron, and zinc.
• Avoid tight hairstyles or excessive heat styling.
• Use gentle, chemical-free hair care products.
• Stay hydrated to support overall health.
• Try to massage your scalp regularly to improve blood circulation to your hair follicles.
• Consider compounded treatments like finasteride and minoxidil or dutasteride and minoxidil combination hair loss solutions. Contact Courier Pharmacy for your FREE hair loss consultation. Our team of prescribers can guide you to the best solution for your hair loss or even develop a bespoke solution tailored to your needs.

What you should know

Mounjaro’s common side effects, which may affect up to 1 in 10 people, include injection site reactions, dizziness, low blood pressure, stomach pain, indigestion, bloating, burping, gas, reflux, and hair loss. These side effects are usually mild and improve as your body adjusts to the medication. However, if symptoms persist or worsen, contact your doctor for advice.

Managing fatigue caused by Mounjaro

Fatigue is a common side effect some people experience while using Mounjaro (tirzepatide). Feeling tired can be frustrating, but there are simple steps you can take to boost your energy and feel better.

Tips to manage fatigue

• Try Coenzyme Q10 (CoQ10): This supplement can help your cells produce more energy and fight fatigue [14]. For more information about compounded CoQ10 buccal solutions, contact us to learn how you can get one month free when purchasing Mounjaro.
• Stay hydrated: Drink plenty of water throughout the day to keep your body running smoothly.
• Eat a balanced diet: Include whole foods like vegetables, lean proteins, and healthy fats in your meals to fuel your body.
• Get moving: Gentle physical activities like walking or yoga can improve your energy levels and overall health.
• Stick to a sleep routine: Aim for 7-8 hours of good-quality sleep each night, and try to go to bed and wake up at the same time every day.
• Cut back on caffeine and alcohol: These can mess with your sleep and leave you feeling more tired.
• Take breaks during the day: Short, regular breaks can help prevent burnout and keep you focused.
• Talk to your doctor if needed: If your fatigue doesn’t improve, it’s important to check with your doctor to rule out any underlying health issues.

What you should know

Fatigue caused by Mounjaro is usually temporary and can often be managed with small lifestyle changes. However, if it continues or gets worse, don’t hesitate to consult your doctor for advice.

Mounjaro – uncommon side effects

Uncommon side effects of Mounjaro (tirzepatide) can affect up to 1 in 100 people. While they don’t happen to most users, it’s important to know what to look out for and how to respond.

Changed sense of taste

Some people may notice that food tastes different while using Mounjaro. This might make eating less enjoyable or reduce your appetite. Usually, this side effect improves as your body adjusts to the medication.

Increased heart rate

A faster heart rate or pulse can sometimes occur, although this is more common when Mounjaro is used to manage diabetes rather than for weight loss.

Elevated pancreatic enzymes

Mounjaro can sometimes cause an increase in certain pancreatic enzymes, such as amylase, which may indicate a pancreas issue. Your doctor may monitor this through blood tests.

Gallstones

Gallstones are hardened deposits of bile that can form in the gallbladder. They often don’t cause symptoms unless they block the bile ducts, leading to sharp stomach pain, especially after eating fatty foods.

Gallstones can trigger sudden, intense abdominal pain that typically lasts between 1 to 5 hours, although it may occasionally last only a few minutes. The pain is often felt: in the middle of the abdomen, just below the ribs on the right side – it can also radiate to the side or shoulder blade.

Other symptoms include fever, chills, and confusion. If you experience sudden, severe stomach pain, contact your doctor immediately.

Injection site pain

Some users may feel discomfort, redness, or swelling where the injection is given. To reduce pain, try rotating injection sites, cleaning the area before injecting, or applying ice to numb the spot beforehand.

Increased calcitonin levels

Mounjaro may cause higher levels of calcitonin, a hormone that helps regulate calcium in the blood. Elevated levels are rare but may require monitoring by your doctor.

Cholecystitis (gallbladder infection)

This is an infection or inflammation of the gallbladder, causing severe pain in the upper right stomach, fever, or yellowing of the skin or eyes (jaundice). If you notice these symptoms, seek medical attention immediately, as it may require urgent treatment.

Mounjaro – serious side effects

Thankfully, serious side effects of Mounjaro are uncommon or even rare. Here’s what you should know:

Uncommon serious side effects (1 in 100 people)

• Acute pancreatitis: This is when the pancreas becomes inflamed, leading to severe stomach or back pain that doesn’t go away. If you experience this, contact your doctor or visit A&E immediately.

Rare serious side effects (1 in 1,000 people)

• Severe allergic reaction (anaphylaxis or angioedema): This includes symptoms like difficulty breathing, swelling of the face or lips, and trouble swallowing. This is a medical emergency. Call 999 or go to A&E right away. Bring your medication packet and let healthcare professionals know you’re taking Mounjaro.

Reporting side effects

If you experience any side effects, even those not listed in the Mounjaro patient information leaflet, it’s important to let someone know. You can:

• Speak to your doctor, pharmacist, or nurse.
• Report side effects directly through the Yellow Card Scheme at www.mhra.gov.uk/yellowcard or via the “MHRA Yellow Card” app on Google Play or the Apple App Store.

Reporting helps improve the safety of medications for everyone.

When do Mounjaro side effects start?

Most side effects occur when you first start using Mounjaro or when your dose increases. Common symptoms like nausea, vomiting, or diarrhoea often improve within a few days to weeks as your body adjusts. If these symptoms don’t go away or get worse, consult your doctor for advice.

What you should know

Uncommon side effects of Mounjaro are rare but can sometimes be serious. Always monitor your symptoms and don’t hesitate to seek medical help if you’re unsure. Early action can prevent complications and ensure you stay safe while using the medication.

Mounjaro and cancer

There has been some concern about whether Mounjaro (tirzepatide) and similar medications could increase the risk of thyroid cancer [15]. Let’s break it down in simple terms so you can understand the facts.

Mounjaro and thyroid cancer

The concern about Mounjaro and thyroid cancer comes from studies done on rodents. In these studies, high doses of GLP-1 drugs, like Mounjaro, caused thyroid tumours in the animals [16].

However, humans and primates are different from rodents because we have very few, if any, GLP-1 receptors on our thyroid cells [17]. This means the risk seen in rodents doesn’t necessarily apply to people.

A large study published in the BMJ in April 2024 followed over 145,000 people using GLP-1 medications, including Mounjaro, for nearly four years [18]. The researchers found no significant increase in thyroid cancer risk compared to people using other diabetes medications. The study concluded that the risk of thyroid cancer with GLP-1 drugs is minimal and unlikely to be a concern for humans.

What should you do if you’re worried about Mounjaro and cancer?

If you’re using Mounjaro or thinking about starting it, here are some steps to keep in mind:

• Stick to your treatment plan: For most people, the benefits of Mounjaro in managing weight or diabetes far outweigh any potential risks.
• Talk to your doctor: If you or your family has a history of medullary thyroid cancer (MTC) or multiple endocrine neoplasia type 2 (MEN-2), let your doctor know before starting Mounjaro.
• Stay alert for symptoms: Watch out for lumps in your neck, trouble swallowing, or any other unusual symptoms. If you notice these, contact your doctor immediately.

Mounjaro side effects conclusion

Mounjaro is a highly effective medication for weight loss and diabetes management. Most side effects are mild and temporary, but it’s important to monitor how your body reacts.

If you experience severe side effects, like pancreatitis or an allergic reaction, seek immediate medical attention.

If you’re unsure about anything or have concerns, contact your healthcare provider or book a FREE consultation with the team at Courier Pharmacy.

Frequently asked questions about Mounjaro

Can I take Mounjaro with levothyroxine?

There are no confirmed interactions between Mounjaro and levothyroxine, but always monitor your thyroid levels and discuss with your doctor [19].

Can I drink alcohol while using Mounjaro?

It’s best to limit alcohol while taking Mounjaro since it can increase side effects like nausea or dizziness [20].

Does Mounjaro cause hair loss?

Hair loss has been reported in about 5% of users, though it’s unclear if this is due to Mounjaro or rapid weight loss [13].

Does Mounjaro cause body aches?

Although not officially listed in the potential side effects associated with Mounjaro, body aches can occur if you are low on magnesium. Since Mounjaro suppresses your appetite, if you are not careful to make sure that you are getting all the nutrients and vitamins your body needs, you may suffer from body aches. Supplementing with magnesium can help ease the symptoms of body aches [21].

Does Mounjaro cause sulphur burbs?

Unfortunately, sulphur or eggy burbs are listed as a side effect of Mounjaro. This is due to Mounjaro slowing the transit time of food in the gut, meaning there is more time for the gut bacteria to ferment the food, leading to the production of these wonderful smelling burbs [22]. You can reduce the production of eggy burbs by reducing your intact of sulphur containing foods.

Can Mounjaro cause depression?

While not listed as an official side effect, more research is required to confirm this due to some conflicting reports [23]. Hence, if you are taking Mounjaro, you should be vigilant for any changes in your mental health.

What is the Mounjaro fifth dose?

Mounjaro only contains four doses. There may be some residual Mounjaro left in the pen after you have injected four doses, but this is there to provide a buffer to make sure four doses are delivered. The remaining amount should not be injected as it is not an accurate dose [24].

Does Mounjaro cause thyroid cancer?

There’s no strong evidence that Mounjaro causes thyroid cancer in humans. Concerns mostly come from animal studies, which don’t directly apply to people [25].

Courier Pharmacy Mounjaro weight loss

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This content was created by our Medical Mojo team to provide general information and is not a substitute for professional medical advice. For personalised recommendations about your health, always consult with your doctor or healthcare provider.

References:

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