Switching weight loss medications

Mounjaro and Wegovy work differently in the body, so their doses don't translate directly to one another. Currently, there isn't any published research that shows how to convert a dose from one treatment to another.

Because of this, switching between them isn't about finding an "equivalent" dose. Instead, your prescriber focuses on:

• How you've responded to treatment so far
• How well you've tolerated it, particularly when it comes to side effects
• Your long-term goals and individual health profile

Everyone responds differently. If you switch from Mounjaro to Wegovy, you may need to start at a lower dose and build up again. Your prescriber will explain your options and help you decide the best next step.

There are several reasons why you and your prescriber may choose to switch between Mounjaro and Wegovy:

• Availability of medication, to help you continue treatment without interruption
• Tolerance, if you've experienced side effects that are difficult to manage on one treatment
• Personal preference, as some people prefer one medication's delivery system or how it fits into their routine

Whatever the reason, our clinically-led team will create a personalised transition plan to help you maintain progress and minimise side effects.

Many people stay on their current treatment. If a change is needed, your prescriber will help you switch safely.

Switching between weight loss medications is not a simple swap. Mounjaro (tirzepatide) and Wegovy (semaglutide) work differently in the body and use different dose strengths. Because of this, no research or chart shows how to match one dose to the other.

If you switch medications, your prescriber focuses on what is safest for you and how well your body tolerates the medication, rather than trying to match your previous dose or results.

This usually means starting Wegovy at a lower dose and slowly increasing it over time.

Mounjaro (tirzepatide)

• Mimics two naturally occurring hormones in the body (GIP and GLP-1)
• Uses a wider range of doses (up to 15 mg)

Wegovy (semaglutide)

• Mimics one hormone (GLP-1)
• Uses a different range of doses (from 0.25 mg to 2.4 mg)

Another way to think about it is like driving two different cars.

Wegovy is a car with a set number of gears, and you move up through them gradually as your body adapts.

Mounjaro is a different car with more gears available, and those gears work differently because the engine is designed differently.

You can't compare "third gear" in one car with "third gear" in another and expect the same speed or feel.

In the same way, Mounjaro and Wegovy have different dose ranges and work differently in the body. The same dose number does not mean the same strength, effect, or weight loss results.

In most cases, yes. Switching between Mounjaro and Wegovy is generally well-tolerated when done under proper clinical supervision.

Importantly, you don't need to stop treatment for a "wash-out" period. If you've been tolerating one medication well, you can take your final scheduled dose one week and begin the new medication the next.

If switching medications is right for you, the goal is to move you over safely and reduce the chance of side effects.

Your prescriber will look at things like:

• The dose you were on before
• How long you've been taking it
• Any side effects you had
• Your overall health
• The dosing plan for new medication

Using all this information, your prescriber will choose a safe starting dose for the new medication. They follow evidence-based guidance and use their professional experience to make sure the dose is right for you.

Mounjaro and Wegovy work slightly differently in the body. Because of this, you may feel different changes in appetite, weight loss, or side effects after switching.

Some people notice very little difference. Others may feel stronger or weaker effects. Switching medications does not guarantee the same results you had before.

If you have any concerns during the switch, your prescriber is available to support you and make changes if needed.

This short video addresses the key side effect differences between Wegovy and Mounjaro, and how to manage them.

It's possible to switch back to Mounjaro if Wegovy isn't working as well for you, and vice versa.

For example, if you switch to Wegovy and later decide to return to Mounjaro, you may not be able to go straight back to your previous highest dose. This depends on how much time has passed and the dose schedule that needs to be followed safely.

Your prescriber will monitor how you respond and adjust your dose if needed. Everyone's results are different, and treatment decisions are always made with your safety in mind.

If you have questions about switching, your MedExpress prescriber can explain what to expect and how your treatment will be managed.

• Try to stay consistent with your weekly injections and avoid missing doses where possible
• Keep a note of any side effects and share these with your clinical team
• Weight loss takes time. Clinicians recommend steady, sustainable progress
• Support your treatment with regular meals, movement, and good sleep habits

Every treatment plan is overseen by our clinical team. We'll review your medical history, current health, and how you've responded to previous treatment before recommending next steps.

Our clinicians are here to offer ongoing advice and guidance, helping you manage your treatment safely and with confidence.