Exploring the differences between Mounjaro vs Ozempic

In the last couple of years, names like Ozempic and, more recently, Mounjaro have become a topic of conversation in many social circles, medical settings, and in the media.

While you have probably heard of some of these types of drugs — and might even be interested in them yourself — you might not know much about how they actually work. Understanding medication before you start taking anything is important, but it can be quite complex and confusing — so that's where we come in.

In this article, we will discuss Ozempic and Mounjaro, how they work, what they are approved for, and any potential side effects you might need to know about.

What is Mounjaro?

Mounjaro, which contains the active ingredient tirzepatide, is an injectable medicine that was designed for adults with type 2 diabetes [1]. It is typically prescribed alongside a healthy diet and exercise to help manage or lower blood sugar levels.

Mounjaro is also prescribed as a weight loss medication for those dealing with obesity and overweight. It is a glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptor agonist and this dual-action treatment can lead to more significant weight loss outcomes.

It has a recommended starting dose of 2.5mg, which can later be increased to 5mg, and the maximum recommended dose is 15mg. The medication is administered through a once-a-week injection, and can only be purchased by patients after a healthcare provider prescribes it.

How does Mounjaro work for weight loss?

For people with type 2 diabetes, Mounjaro helps support blood sugar control by activating both glucose-dependent insulinotropic polypeptide and glucogen-like peptide 1 pathways.

These are the 2 primary incretin hormones that are secreted from your intestine when you ingest glucose or nutrients and stimulate insulin secretion from pancreatic β cells [2].

As well as increasing your insulin release, they also decrease the amount of glucose your liver produces, which means a lower blood glucose level — which is important for those with type 2 diabetes or issues with above-average blood sugar levels.

The medication can also improve insulin sensitivity and lead to a decreased appetite and less food being eaten. Research into the use of this medication for treating type 2 diabetes found it led to improvement in blood glucose management and weight loss benefits.

The combination of Mounjaro's GLP-1 and GIP makes it effective at promoting weight loss by controlling appetite, promoting fat loss and preventing fat gain, which is why Mounjaro is one of the medications prescribed in the Juniper Programme.

Want to see real results? Explore Mounjaro before and after transformations.

How effective is Mounjaro for weight loss?

According to clinical trials, Mounjaro is the most effective treatment for weight loss that is available right now. One study of over 2,500 patients from July 2022 found an average of up to 20.9% body weight loss in patients on GLP-1/GIP after 72 weeks [3].

In the same study, up to 90.9% of patients were able to achieve at least 5% weight loss, up to 83.5% were able to achieve at least 10% weight loss and 56.7% were able to achieve at least 20% weight loss in 72 weeks of treatment.

What is Ozempic?

Ozempic and Mounjaro have some similarities, but they are different medications. Ozempic is a semaglutide injection and comes in 0.5 mg, 1 mg, or 2 mg weekly doses [6].

The maximum dose is 2mg weekly, and the medication should always be taken as prescribed by your healthcare provider.

Similar to Mounjaro, Ozempic was designed as a treatment to help lower blood sugar in patients with type 2 diabetes and this is how the medication is licensed for use in the UK. It is also often prescribed to reduce the chances of major cardiovascular events (such as heart attack or stroke) for adults who have type 2 diabetes and heart disease.

However, in recent times, Ozempic has also been prescribed off-label as a weight loss drug. But, with the advent of Wegovy, a medication that also contains semaglutide and is licensed as a weight loss treatment in the UK, the use of Ozempic for weight loss is largely unnecessary.

Alongside Mounjaro, the other medication option in the Juniper Programme is Wegovy, which is another incredibly effective weight loss treatment.

A higher dose of a type of GLP-1 medication has been shown in clinical trials to be more effective for weight loss than some of its alternatives. The study from 2021 looked at 1,961 obese and overweight adults who were randomly assigned the GLP-1 injections or a placebo [4].

After 68 weeks, those taking the GLP-1 lost an average of 15.3kg, whereas the placebo group lost an average of 2.6kg. Participants also implemented lifestyle changes, particularly in their diet and exercise habits, which helped enhance the impact of GLP-1 medication as a weight loss drug.

However, more recent data on Wegovy’s 7.2mg dose show average weight loss of 20.7% after 72 weeks, putting it nearly on par with Mounjaro in terms of effectiveness [11].

How does Ozempic work?

To understand how Ozempic works, let's look at its key ingredient, semaglutide. Semaglutide mimics a hormone and stimulates insulin production when your blood sugar levels increase [5].

It also helps prevent your liver from making and releasing too much sugar [6].

As these hormone levels rise, another effect is that it sends molecules to your brain telling you you're full and slows down digestion — and these side effects mean that semaglutide often leads to weight loss. Wegovy works similarly but comes in higher doses than Ozempic.

What are the side effects of Mounjaro vs Ozempic?

Like any medication, both Ozempic and Mounjaro can have side effects.

Common side effects of Mounjaro include:

• Nausea
• Diarrhoea
• Decreased appetite
• Vomiting
• Constipation
• Indigestion
• Abdominal pain.

On Mounjaro's packaging, there are warnings about other potential side effects, namely thyroid tumours and thyroid cancer [1]. However, these warnings are based on studies of animals and it is unclear whether this risk is also present in humans [7].

Still, anybody with Multiple Endocrine Neoplasia syndrome type 2 or a family history of medullary thyroid carcinoma is advised not to take Mounjaro.

Other side effects can include inflammation of the pancreas, low blood sugar levels, and kidney problems or kidney failure — although these are a lot less common.

Some users could also experience symptoms of allergic reactions including rash or itching, feeling dizzy, elevated heartbeat, problems breathing or swallowing, and swelling of the face, lips, tongue or throat.

The most common side effects of Ozempic are [8]:

• Nausea
• Stomach pain
• Constipation
• Vomiting
• Diarrhoea
• Fatigue
• Headaches

Like Mounjaro, Ozempic can also cause more serious issues (although rarer) including thyroid tumours or cancer, changes in vision, pancreatitis, low blood sugar levels, kidney issues, gallbladder problems and severe allergic reactions.

Can you take Mounjaro and Ozempic together?

It is not recommended to take more than one GLP-1 medication at a time.

These drugs can also interact with other medications you might be taking, so it is always best to speak with your doctor and make sure they are aware of all of your medications and any other health conditions before you begin taking a new drug.

Can you switch from Ozempic to Mounjaro?

As long as you are doing so under the guidance of a healthcare provider, it is generally safe to switch from one medication to another, as long as you can tolerate the new one.

If you are switching, it is best to stop taking one type of medication, and then start the new type one week later to make sure you are not going over the maximum weekly dose of the active ingredient or GLP-1 agonist [9].

If you have had an adverse reaction previously, you may want to wait longer before starting the new medication.

Can you switch from Mounjaro to Wegovy?

Yes! It is both safe and straightforward to switch from Mounjaro to Wegovy.

When making the switch, Juniper patients don’t need to restart at the lowest dose. If clinically appropriate, they can continue at a higher dose aligned with recent treatment history.

Plus, our switching protocol has only a 7-day gap between medications, compared to 28 days with most other providers. Our clinical oversight ensures safe, effective transitions — helping patients maintain momentum without compromising care.

You can switch in a few easy steps. Simply answer some quick questions about your medical history and goals and choose whether to continue on your current medication or switch to an equivalent dosage in the same trusted GLP-1 class of medications. From here, our clinicians will work with you to find the best treatment plan.

How do I know which weight loss medication is right for me?

Figuring out which medication is right for you, or going to a doctor and asking for a GLP-1 medication might be a little overwhelming.

This is where the Juniper Programme is especially helpful. The programme begins with a quiz to assess your health and needs, and prescribers will then assess your eligibility to make sure you are a suitable candidate for the medication.

Our programme provides access to proven weight loss medication tailored to your health history and goals — never a one-size-fits-all approach. With an integrated app, you can track your weight and habits, stay connected to your care team, and access unlimited medication adjustments, personalised support, and expert guidance at no extra cost. We also provide structured tools to help you build lasting habits and offer ongoing support once you reach your goal weight.

Kickstart your weight loss journey with Wegovy, a groundbreaking weight loss injection that mimics the GLP-1 hormone to help control cravings, delay stomach emptying, and keep you feeling fuller for longer.

We help you make lifestyle and habit changes and we’re in it with you for the long run; having helped thousands of women achieve their weight loss goals.

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