Wegovy vs Mounjaro: What's the Difference

Arguably the most popular way to manage weight today is through once-weekly weight loss injections. Two of the most commonly compared treatments on the UK market are Wegovy and Mounjaro. Whilst both treatments offer effective, long-term success, they work through different mechanisms, and suit different patients.

Here we’ll break down everything you need to know about Wegovy vs Mounjaro, including their effectiveness, side effects and how to choose the right option for your health.

Mounjaro vs Wegovy: Quick Comparison at a Glance

Whilst both treatments are administered as a once-weekly subcutaneous injection, the active ingredients within them, and how they work differ:

Mounjaro vs Wegovy Weight Loss: Which is More Effective?

When comparing Wegovy vs Mounjaro for weight loss, both have shown impressive results in clinical trials, helping many lose significant weight when used alongside sustainable lifestyle modifications.

• Wegovy activates the GLP-1 receptor and in doing so, leads to slower digestion and earlier feelings of fullness, leading to reduced food intake.

• Mounjaro activates GLP-1 but also GIP. This dual approach further slows digestion whilst regulating blood sugars, preventing the energy dips that cause intense food cravings.

A clinical trial comparing the effectiveness of both treatments found:

• Mounjaro led to an average weight loss of 20.2%.

• Wegovy led to an average weight loss of 13%.

Despite this, results from the trial are an average value, results can vary between individuals and many patients have found they respond better to Wegovy.

Wegovy vs Mounjaro Dosage Comparison

For both medicines, treatment is started at the lowest (initiation) dose and stepped up gradually. This slow titration allows the body to adjust to treatment, reducing the risk of side effects. Dose increases are made no sooner than every 4 weeks if necessary.

Wegovy starts at 0.25mg weekly, increasing through 0.5mg, 1mg, 1.7mg up to the maximum maintenance dose of 2.4mg or the recently approved 7.2mg.

Mounjaro starts at 2.5mg weekly, increasing through 5mg, 7.5mg, 10mg, 12.5mg and a maximum of 15mg.

With either treatment, your clinician may suggest maintaining at a lower dose for longer, if you continue to see benefit with minimal or tolerable side effects.

Both treatments are equally convenient to take, as they only need to be injected once-weekly. However, if you struggle with needles, the newly launched Wegovy tablets may be a more suitable alternative. Unlike regular tablets, Wegovy tablets must be taken in a specific manner, to ensure the drug is adequately absorbed.

Wegovy vs Mounjaro Side Effects and Safety

As with any medication, both Wegovy and Mounjaro can cause side effects, though not everyone gets them. With both treatments, side effects are more likely upon starting treatment or after a dose increase and usually go away on their own as the body adjusts.

Most common side effects of include:

• Nausea and vomiting.

• Diarrhoea or constipation.

• Heartburn, bloating and stomach gas

• Headaches (usually due to dehydration)

These side effects are common to both treatments and occur due to how they interact with the gastrointestinal system. Data from trials however, suggest Mounjaro is slightly better tolerated by patients, though this is not true for everyone.

Both treatments carry a risk of serious side effects, requiring immediate medical attention, including:

• Acute pancreatitis

• Gallstones

• Severe allergic reactions

Mounjaro vs Wegovy UK Eligibility

In the UK, all weight loss injections are prescription-only (POM). They can only be accessed by patients who meet the safe clinical criteria.

Here at Quick Meds, this is done by completing an online consultation which asks about your weight, your medical history and if you are taking other medication. A GPhC-registered prescriber then reviews your responses for clinical eligibility.

You may also be required to upload a fully-clothed photo of yourself which serves as a way to verify your weight - in line with current prescribing regulations.

To qualify for a private prescription for either Wegovy or Mounjaro, you must meet the following baseline criteria:

• A BMI of 30 or above - classified as obese.

• A BMI of 27 to 29.9, with a weight-related health condition.

A weight-related health condition is any condition which is made worse by excess weight, such as high blood pressure, high cholesterol or sleep apnoea.

NHS vs Private Access

Whilst the criteria for eligibility is the same, obtaining a prescription through the NHS is restricted, due to funding restrictions.

On the NHS, criteria is generally higher, with higher BMI requirements and multiple co-morbidities. In a nutshell, the NHS will only subsidise the cost of treatment for patients with the highest clinical need.

Private clinics offer greater access, assessing individual patients based on the licensed criteria, without the burden of NHS waiting lists. When obtained privately, patients bear the upfront cost of the treatment.

Wegovy vs Mounjaro Cost and Access

The cost of treatment is heavily influenced by the dose you purchase and where you buy treatment from.

Initiation doses tend to be most affordable, with cost increasing with doses - this is due to a higher volume of active ingredient. In the UK, Wegovy is usually more affordable, whilst Mounjaro’s dual action formulation attracts a premium price.

Some online pharmacies charge more for treatment, whilst others include the cost of a consultation free of charge within the treatment price.

To find precise costs for every available dose, please visit our pricing information page.

Can You Switch Between Wegovy and Mounjaro?

Yes, it is possible to switch between treatments. Patients often switch treatments due to weight loss progress which has stalled, side effects or affordability.

Importantly, as the treatments contain different active ingredients, there is no equivalence dose available. For those who are on a high dose of one treatment, they will not be able to switch straight to the highest dose of the other treatment.

When switching, patients must start at the initiation dose and titrate up as you did with your initial treatment. This process allows the body to adjust safely, reducing the risk of side effects.

Which Is Better: Mounjaro or Wegovy?

There is no one-size-fits-all approach. Both are effective treatments, clinically proven for weight loss. The right choice for you depends on your medical history, how your body responds to the medicine and affordability.

Who May Prefer Wegovy?

• Patients who are looking for cardiovascular health benefits - Wegovy is licensed to reduce the risk of heart attacks and stroke in overweight patients.

• Patients using oral contraceptives - Wegovy does not interact with oral contraceptive pills.

• Patients who are looking for a tablet form - Wegovy tablets have been approved for those who want to transition away from injections.

Who May Prefer Mounjaro?

• Patients who need extra appetite control. Mounjaro’s dual action mechanism has been proven to produce greater average weight loss.

• Those prone to side effects. Evidence suggests Mounjaro may be slightly better tolerated for some.

• Those looking for maximum waist circumference reduction. Clinical data highlights excellent results in reducing deep abdominal fat.

Next Steps

Before starting any weight loss injection, you must complete a clinical assessment. At Quick Meds, this involves completing an online consultation, which is assessed by our GPhC-registered prescribers for safety and eligibility. This ensures your chosen treatment plan is safe, legal and tailored to your goals.