Switching from Wegovy to Mounjaro, with UK doctor approval

If you're considering switching from Wegovy and Mounjaro, a UK-registered doctor will review your current treatment, dosage, and medical history to confirm whether a swithc is safe and appropriate for you, and guide you through what to expect before approving any change.

Yes, you may be able to switch from Wegovy to Mounjaro if a doctor confirms it's safe and appropriate for you.

Switching from Wegovy to Mounjaro is not like-for-like change you may not experience the same effect (which can improve with dose titration). A UK registered doctor must review your medical history, current Wegovy dose, and how you've responded to treatment before approving any switch.

Why a medical review is needed

Wegovy and Mounjaro contain different active ingredients and work slightly differently in the body. Because of this, switching requires clinical oversight to reduce the risk of side effects and ensure the new treatment is suitable for you.

When switching may be appropriate

Switching may be considered if:

• You've not achieved expected results on Wegovy
• You're experiencing side effects that are difficult to manage
• Your response to Wegovy has changed over time

Switching works by stopping Wegovy, waiting 7 days, then starting Mounjaro on a weekly schedule, following your doctor's guidance.

After discussing the switch with your doctor, you'll follow a short transition process to allow Wegovy to leave your system before starting Mounjaro.

Step-by-step: switching safely

1) Finish your last Wegovy pen, then stop taking Wegovy

2) Wait 7 days before starting Mounjaro. This gap is important, as taking the two medications too close together can increase the risk of side effects.

3) After 7 days, start your first dose of Mounjaro. You'll then continue taking your injections once a week, on the same day and time, as you did with Wegovy. Your starting dose will depend on your previous Wegovy dose and whether you experienced any side effects.

Wegovy to Mounjaro conversion chart

This table shows the maximum Mounjaro dose you can start on when switching from your current dose of Wegovy:

If you are experiencing side effects

Let your doctor know if you've had side effects on Wegovy before switching.

This may affect which Mounjaro dose you start on and whether it's safe to switch straight away.

For more information on Mounjaro dosages

Take a look at our Mounjaro dosages for weight loss guide.

Some people choose to switch from Wegovy to Mounjaro because fo differences in effectiveness, side effects or the results they're seeing over time.

There are a few reasons why switching may be considered, depending on how your body responds to treatment.

Effectiveness

Clinical trials show that Mounjaro is associated with greater weight loss. At the highest maintenance dose of 15mg per week, Mounjaro helps people lose an average of 22.5% of their starting body weight.

Wegovy has been shown to help patients lose up to 21% average of their starting weight on the highest maintenance dose of 7.2mg after 72 weeks. On the maintenance dose 2.4 mg of Wegovy it is shown that patients can lose up to 17% of their starting weight after 68 weeks.

Side effects

Both weight loss injections can cause side effects. If you're experiencing side effects on Wegovy, you may want to switch to Mounjaro. However there is no guarantee that switching will prevent side effects, as everyone reacts differently to these medications.

If you are having side effects with Wegovy that are not getting better, you'll likely need to start on the lowest dose of Mounjaro if you switch. If you have severe side effects, your doctor may recommend trying a different weight loss treatment altogether.

Results

If you are not experiencing the weight loss you'd hoped for while using Wegovy, switching to Mounjaro may be an option.

If you have not lost at least 5% of your starting weight within 6 months of starting Wegovy, your doctor may suggest that you stop using.

Anyone who meets the criteria for both weight loss medications may be able to switch from Wegovy to mounjaro, if a doctor confirms it's appropriate.

If you are already taking Wegovy, you will likely be able to use Mounjaro. Before helping you switch medications, your doctor will check that you meet the eligibility criteria.

Eligibility criteria

You may be able to switch if you:

• Are not breastfeeding or pregnant
• Do not have a pre-existing medical condition that makes Mounjaro unsuitable, such as an allergy to the active ingredient tirzepatide
• Are over 18 years old
• Are not taking any medications that may interact with Mounjaro

After switching from Wegovy to Mounjaro you may notice temporary changes in your appetite as Wegovy leaves your system and your body adjusts to the new medication.

Temporary appetite changes

Any increase in appetite is usually temporary.

Mounjaro works in a similar way to Wegovy by binding to the glucagon-like peptide-1 (GLP-1) receptors. As your dose of Mounjaro increases, you should begin to notices positive changes in your appetite again.

Changes are not withdrawl symptoms

It's unlikely that you'll experience Wegovy withdrawal symptoms.

Instead, you may notice appeite changes, body changes, or stomach upset. These are signs that your body is returning to baseline rather than symptoms of withdrawal.

What happens as your dose increases

As your Mounjaro dose is gradually increased and your body gets used to the medication, you're more likely to notice improve weight loss results.

If Mounjaro treatment is suitable for you, switching from Wegovy to Mounjaro may be worth considering.

Mounjaro is often associated with greater weight loss and may be a more effective option for some people. For this reason, switching is a reasonable option if your doctor confirms that the treatment is appropriate.

If you're interested in making the change from Wegovy to Mounjaro, you can begin a consultation with one of our doctors to check whether Mounjaro is suitable for your individual circumstances.

If you're unsure whether switching from Wegovy to Mounjaro is the right choice, you're not alone. Deciding to change treatment can depend on how well Wegovy has worked for you so far, how manageable any side effects have been, and what your weight loss goals are.

Some people continue with Wegovy because it's working well and is well tolerated. Others consider switching if weight loss has plateaued or if side effects have become difficult to manage over time.

A UK doctor can review your treatment history and help you weigh up whether switching to Mounjaro makes sense, or whether staying on Wegovy or exploring another option may be more appropriate.

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