Switching from Mounjaro to Wegovy: What You Need to Know
Introduction
The rising costs of Mounjaro in the UK have prompted many people currently using it to consider Mounjaro alternatives, especially Wegovy UK. But switching from Mounjaro to Wegovy isn’t a simple swap , it requires careful clinical guidance, dose calculations, and monitoring to maintain safety and treatment momentum. In this article, we’ll walk you through how to switch safely, what to expect, and how MediClick Pharmacy can support your transition for weight loss injections, GLP‑1 treatments, and Wegovy consultation in the UK.
1. Why Patients Are Switching: Rising Costs & Other Factors
- As of late 2025, Mounjaro’s UK list price is increasing significantly (e.g. up to +170 % for high doses)
- That price hike is driving many to explore Mounjaro to Wegovy transitions as a more cost‑viable path
- Other reasons: side effect tolerability, easier dosing schedules, supply considerations, or personal preference.
It’s important to stress: patients should not self-switch and always consult a qualified prescriber. The MHRA has emphasised that switching between GLP‑1 medicines must be supervised to avoid risks.
2. Understanding Mounjaro vs Wegovy: Mechanism & Dosing Differences
Mechanism & class
- Mounjaro (tirzepatide) is a dual GIP + GLP‑1 agonist , it acts on both hormone pathways.
- Wegovy (semaglutide) is a GLP‑1 agonist only.
Because of this difference, the two drugs are not directly interchangeable despite some overlap in their appetite‑suppression profiles.
Dosing schedules
- Mounjaro is typically escalated over weeks (e.g. 2.5 → 5 → 7.5 → 10 → 12.5 → 15 mg in some protocols)
- Wegovy starts lower and increases more gradually: 0.25 → 0.5 → 1.0 → 1.7 → 2.4 mg (maintenance)
When switching, your prescriber may allow you to start Wegovy at a higher dose than the default beginner dose, especially if you tolerated Mounjaro well.
3. How to Switch: Safe Transition Protocols
Timing & interval
- A common approach: take your final Mounjaro dose, then wait ~7 days before beginning Wegovy. This gives a “gap” that mitigates overlapping side effects.
- Many clinicians consider that a 7‑day interval is sufficient (rather than a long “washout” period) because both drugs have relatively long half‑lives.
- However, each patient’s plan should be personalised based on tolerability, dose history, and medical conditions.
Selecting starting Wegovy dose
- If you were on a low or moderate Mounjaro dose, your clinician may recommend starting Wegovy at a conservative dose (e.g. 0.25 or 0.5 mg) and titrating upward.
- If you were already on a higher Mounjaro dose and tolerated it well, your prescriber might allow you to begin at an intermediate or higher Wegovy dose (e.g. 1.0 mg or 1.7 mg) to maintain momentum.
- After initial dosing, standard Wegovy titration (every 4 weeks) applies, as tolerated.
Monitoring & adjustments
- Close follow-up is critical in the first 4–12 weeks, watching for side effects (nausea, constipation, GI issues), appetite changes, weight trajectory, and metabolic markers.
- Dose adjustment, pause, or slowing titration may be required if side effects emerge
4. What to Expect: Efficacy, Side Effects & Differences
Weight loss potency
- Because Mounjaro has an added GIP pathway, some patients achieve slightly more aggressive weight loss in trials.
- But Wegovy has strong evidence in obesity trials (e.g. STEP studies) showing weight reductions of ~15–20 % in many participants.
Side effects & tolerability
- GI side effects are the most common: nausea, constipation, diarrhoea, indigestion, bloating.
- You may experience a “new set” of side effects or a re‑onset of milder GI symptoms during the first few weeks on Wegovy.
- Because you’re switching, transient increases in hunger or fluctuations can occur ,but most patients adapt.
- If side effects become problematic, clinicians may slow the titration, reduce doses, or use supportive therapy (e.g. antiemetics).
- GI side effects are the most common: nausea, constipation, diarrhoea, indigestion, bloating.
Maintaining continuity & weight trajectory
- One challenge: if you drop back to a low starting dose, you might lose momentum or see weight “stall” briefly before re-escalation. A reason why starting at a higher dose (if safe) is appealing.
- It’s vital to maintain diet, exercise, behavioural strategies during transition to reduce disruptions.
Some patients worry about “withdrawal” from Mounjaro; but because both act on GLP‑1 to some extent, significant withdrawal is uncommon.
- One challenge: if you drop back to a low starting dose, you might lose momentum or see weight “stall” briefly before re-escalation. A reason why starting at a higher dose (if safe) is appealing.
5. Key Considerations & Risks When Switching
- Always consult a qualified prescriber switching GLP‑1 treatments without supervision increases risk of side effects or suboptimal dosing. The MHRA has issued new guidance emphasising that point.
- Differences in licensed uses: check whether Wegovy is clinically appropriate for you (your BMI, comorbidities, risk profile).
- Watch for contraindications (e.g. history of pancreatitis, medullary thyroid carcinoma, etc).
- In individuals with type 2 diabetes, glycaemic control and insulin dose adjustments need more careful oversight.
- Monitor for signs of intolerable GI effects, dehydration, or nutritional issues.
- Be realistic: your prescriber may recommend a more cautious transition (slower dose increases) depending on your history.
How MediClick Pharmacy Supports Your Transition
- At MediClick Pharmacy, we provide online pharmacy weight loss support with UK‑based clinical oversight.
- We offer a Wegovy consultation service: through our clinicians, we help assess your suitability, your Mounjaro history, and design a safe transition plan.
- We ensure discreet delivery, dose titration support, regular clinical check-ins, and side effect guidance.
- If needed, we liaise with your GP or specialist (with your consent) to maintain continuity of care.
Our goal: facilitate a smooth, safe switch from Mounjaro to Wegovy so you keep your treatment momentum and avoid unnecessary treatment disruption.
Frequently Asked Questions
1. How to switch from Mounjaro to Wegovy safely?
Work with a prescriber who can plan a 7‑day gap after your last Mounjaro dose, choose your appropriate starting Wegovy dose based on your prior dose and tolerability, and carefully monitor symptoms and weight while titrating in 4‑week steps.
2. Is Wegovy cheaper than Mounjaro in the UK?
Yes , one of the main motivations for switching is cost. The upcoming Mounjaro price increases in the UK are substantial, making Wegovy a more affordable long-term option for many patients.
3. Can I change my weight loss injection prescription?
You can, but only under medical supervision. Your prescriber must review your history, risk factors, and design a safe transition plan. Self‑changing raises risk of side effects and loss of effectiveness.
4. What are the side effects of switching from Mounjaro?
You may see nausea, vomiting, constipation, diarrhoea, or abdominal discomfort again (or a new) when you start Wegovy. These often subside with time. If side effects persist, your clinician may slow titration or adjust dose.
5. Who can prescribe Wegovy online in the UK?
In the private sector, qualified UK prescribers can prescribe Wegovy after reviewing your medical history and suitability. Here at MediClick Pharmacy we have registered prescriber practitioners who can facilitate Wegovy consultation services.