Switching treatments

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

• Availability - ensuring you can continue treatment without interruption.

• Cost – Wegovy is often more cost-effective for long-term use.

• Tolerance – Switching may be advised if you’ve experienced difficult side effects on Mounjaro.

• Personal preference – some people simply prefer one medication’s delivery system or how it feels to take it.

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

In most cases, yes. Both Mounjaro and Wegovy are GLP-1 receptor agonists, which is a type of medication that works in similar ways to regulate appetite and support weight loss. Because of this shared mechanism, switching between the two is generally well-tolerated when done under medical supervision.

Importantly, you don’t need to stop treatment for a “wash-out” period. If you’ve been tolerating Mounjaro well, you can take your final scheduled dose one week and begin Wegovy the next.

There’s no exact “one-to-one” match between Mounjaro and Wegovy doses, but there are clinical guidelines we follow to find the closest safe equivalent. If you’ve been tolerating your current Mounjaro dose without significant side effects, your prescriber will usually start you on the Wegovy dose that provides similar appetite control and treatment effect.

While your exact plan will be individual to you, the transition often looks like this:

1. Last dose of Mounjaro – taken as normal.
2. Seven days later – first dose of Wegovy at your agreed starting strength.
3. Every four weeks – dose increases in line with Wegovy’s titration schedule, unless you and your prescriber agree to remain at a lower dose for longer to manage side effects.

Because both medications work in similar ways, your experience on Wegovy may feel familiar, especially if you tolerated Mounjaro well.

You may notice:

• Changes in appetite – some people find appetite suppression feels slightly different between the two medicines.
• Similar side effects – including mild nausea, constipation or diarrhoea, especially in the early weeks or after a dose increase.
• Weight loss patterns – the rate of weight loss may vary initially, but clinical research shows that by 12 months, Wegovy can deliver comparable results to Mounjaro for many people, especially when taken consistently.

Your prescriber will monitor your progress closely during the first months of treatment and adjust your plan if needed.

You might notice weight loss is slightly slower at first compared to Mounjaro, but most people still achieve meaningful, lasting results with Wegovy. This is especially true when they stay consistent with weekly injections.

Medical professionals often recommend a “slow and steady” approach. This not only supports sustainable weight loss, but can also help reduce side effects such as hair loss or loose skin.

By around six months, the total weight lost on both treatments is often similar. Clinical trial data shows about a 4% difference between the two, and our own MedExpress data suggests the gap can be even smaller, at around 3%

• Stay consistent with your weekly injections. Avoid missing doses where possible.

• Keep track of any side effects and share these with your clinical team.

• Be patient. Slow, steady weight loss is generally recommended by clinicians. After all, weight loss is a marathon, not a sprint.

• Maintain healthy routines around food, movement and sleep to support your medication.

Every switch from Mounjaro to Wegovy is overseen by our clinical team. We will review your medical history and current health, and assess how well you've tolerated Mounjaro so far. We'll always recommend a safe and effective starting dose of Wegovy, and ensure that we provide ongoing support through check-ins, advice and resources to help you adapt smoothly to your new treatment.