The UK's most complete GLP-1 guide
Every Question Answered. Every Side Effect Explained.
- How GLP-1 medications work
- Mounjaro vs Wegovy compared
- Injection instructions
- Side effects & solutions
- What to eat on treatment
- FAQs answered
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Mounjaro and Acid Reflux — Cost and Access in the UK
Acid reflux (gastro-oesophageal reflux disease, or GERD) is a common side effect reported during Mounjaro treatment. This guide explains what acid reflux means as a Mounjaro side effect, how it may affect you, and the two main routes to access Mounjaro in the UK — through the NHS or via private prescription. Understanding both the clinical aspects and the practical access pathways can help you make an informed decision about whether this medication is right for you.
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Enter your height and weight below. Supports both imperial (stone & lbs) and metric (kg). Results include NHS category, healthy weight range, and ethnicity adjustments.
What Is BMI and Why Does It Matter?
Body Mass Index (BMI) is the most widely used screening tool for assessing whether your weight falls within a healthy range. Used by the NHS, GPs, and weight management services across the UK, BMI provides a quick snapshot of your weight relative to your height. The formula is simple: your weight in kilograms divided by your height in metres squared (kg/m²).
While BMI isn't a perfect measure — it doesn't account for muscle mass, bone density, or fat distribution — it remains the standard first step in identifying potential weight-related health risks including type 2 diabetes, cardiovascular disease, high blood pressure, and certain cancers.
The NHS also recommends adjusted thresholds for people of South Asian, Chinese, or Black African heritage — a BMI of 23 or above is classified as overweight, and 27.5 as obese. Our calculator includes this adjustment as a one-click toggle.
UK Prescription Costs and Private Access Routes
Mounjaro is available in the UK through two distinct routes: NHS specialist services and private online prescribing. Private prescription costs for Mounjaro vary depending on the dose and provider, typically ranging from £129 to £320 per month. This reflects the dose you're prescribed — starting doses (2.5 mg) are at the lower end, whilst maintenance doses (15 mg) are at the upper end. Each KwikPen contains four weekly injections, and you'll receive a new pen every four weeks whilst on active treatment. It's important to note that private costs are not regulated, so prices do vary between providers. Always check the total cost upfront, including any consultation fees, which typically range from £30 to £50 per appointment. Use our free GLP-1 weight loss calculator to help you understand potential outcomes and whether Mounjaro aligns with your health goals before committing to any cost.
- Starting dose (2.5 mg): Generally £129–£160 per month
- Maintenance doses (5–15 mg): Usually £180–£320 per month
- Consultation fee: Typically £30–£50 (some providers include this in the first prescription)
- Each KwikPen: Contains 4 weekly doses; one pen lasts 4 weeks
Clinically BackedWeight Loss
No appointments. No waiting rooms. Just care — from a UK-regulated online pharmacy.
How It Works
Three simple steps to understand your weight and take action.
Enter your height and weight in our free calculator. Get your BMI, NHS category, healthy weight range, and ethnicity-adjusted thresholds instantly.
If your BMI suggests you're overweight or obese, explore our GLP-1 calculators to project potential weight loss on Mounjaro or Wegovy.
Use our progress tracker to log your weight weekly, visualise your journey with charts, and stay motivated — all stored privately in your browser.
Free Weight Loss Tools & Guides
Everything you need to understand your weight, explore medication options, and track your progress — completely free.
NHS vs Private Access: How to Get Mounjaro in the UK
NHS route: Mounjaro is available through NHS specialist weight management services (tier 3/4), but access is heavily rationed and varies significantly by region. You'll need a GP referral and may face waiting lists of several months to years. NICE has approved tirzepatide (Mounjaro's active ingredient) for NHS use, but not all ICBs (integrated care boards) commission it. Private route: You can access Mounjaro via a UK-licensed prescriber through an online consultation without an NHS referral. The process typically involves completing a health questionnaire, having a brief video or telephone consultation, and — if approved — receiving a prescription that's dispensed by a GPhC-registered pharmacy. This route is faster (often within days) but requires you to pay the full cost. Consider your budget, timeline, and whether acid reflux side effects are a concern for you before choosing your route.
- Dual GIP/GLP-1 receptor agonist
- Up to 22.5% body weight loss (SURMOUNT-1)
- Weekly injection, dose escalation over 20+ weeks
- Available via private prescription in the UK
- Doses: 2.5mg → 5mg → 7.5mg → 10mg → 12.5mg → 15mg
- GLP-1 receptor agonist
- Up to 15–17% body weight loss (STEP trials)
- Weekly injection, 5-step dose escalation
- NHS & private prescription available
- Doses: 0.25mg → 0.5mg → 1mg → 1.7mg → 2.4mg
Mounjaro vs Wegovy: Head-to-Head
A side-by-side comparison of the two most popular GLP-1 weight loss medications available in the UK.
| Feature | Mounjaro | Wegovy |
|---|---|---|
| Drug class | Dual GIP/GLP-1 agonist | GLP-1 agonist |
| Active ingredient | Tirzepatide | Semaglutide |
| Avg. weight loss | 15–22.5% | 12–17% |
| Key trial | SURMOUNT-1 (2022) | STEP 1 (2021) |
| Max dose | 15 mg weekly | 2.4 mg weekly |
| Escalation period | 20–32 weeks | 16–20 weeks |
| Administration | Weekly injection (pen) | Weekly injection (pen) |
| NHS availability | Private prescription only | NHS & private |
| Approx. private cost | £150–£250/month | £150–£300/month |
| Common side effects | Nausea, diarrhoea, constipation | Nausea, vomiting, diarrhoea |
Data sourced from SURMOUNT-1 and STEP 1 clinical trials. Costs are approximate and vary by provider. Always consult a prescriber.
Am I Eligible for Weight Loss Medication?
In the UK, eligibility for GLP-1 weight loss medications like Mounjaro and Wegovy is based on your BMI and overall health profile.
- BMI of 30 or above (obese)
- Age 18 or over
- No contraindicated conditions
- Committed to lifestyle changes
- BMI of 27 or above
- Plus type 2 diabetes
- Or high blood pressure
- Or obstructive sleep apnoea
Use our BMI calculator to check whether your BMI falls within the eligible range.
How We Built These Tools
Every calculator and guide on myweightcheck is built with accuracy and transparency in mind. Our BMI calculator uses the standard WHO formula with NHS-aligned category thresholds. Our GLP-1 projections are modelled on published clinical trial data from SURMOUNT and STEP studies.
All data stays on your device. We don't require sign-ups, and we don't store your health information on any server. Your progress tracker saves data locally in your browser using localStorage, so only you can see it.
We're based in the UK and our tools are designed specifically for UK users — supporting stone & lbs by default, referencing NHS guidelines, using NICE-approved medication data, and linking to GPhC-registered pharmacies.
Frequently Asked Questions
Common questions about BMI, weight loss medications, and our free UK tools.
What exactly is acid reflux as a Mounjaro side effect?
Acid reflux (GERD) occurs when stomach acid flows back into the oesophagus, causing heartburn or indigestion. On Mounjaro, this happens because the medication slows gastric emptying — food stays in your stomach longer, increasing pressure and acid reflux risk. It's listed as a "common" side effect (affecting up to 1 in 10 people). Most cases are mild and manageable with lifestyle changes or over-the-counter antacids, but if severe, inform your prescriber.
How much does private Mounjaro cost compared to other weight loss injections in the UK?
Private Mounjaro costs typically range from £129–£320 per month depending on dose. Wegovy (semaglutide) costs similarly, around £149–£299 per month, whilst Saxenda (liraglutide) is a daily injection costing roughly £150–£200 per month. Costs vary between providers, so it's worth comparing. NHS costs are zero for eligible patients, but access is limited and waiting times are long in most areas.
Can I get Mounjaro on the NHS for acid reflux management?
Acid reflux is not itself a qualifying condition for NHS Mounjaro — you need to have obesity (BMI ≥30) or overweight (BMI 27–29.9) with weight-related health conditions like type 2 diabetes, hypertension, or sleep apnoea. If you're eligible, NICE has approved tirzepatide for NHS specialist services, but availability depends on your regional ICB. Ask your GP about referral to a tier 3 weight management service in your area.
What's the online consultation process for private Mounjaro, and how long does it take?
You'll complete an online health questionnaire covering medical history, current medications, and lifestyle. A UK-licensed prescriber reviews this (usually within 24 hours) and conducts a brief consultation via video or phone to assess suitability. If approved, a prescription is issued to a GPhC-registered pharmacy, and your Mounjaro is dispatched, typically arriving within 2–5 working days. The entire process often takes 3–7 days from start to delivery.
Should I be concerned about acid reflux if I choose Mounjaro, and can it be managed?
Acid reflux affects roughly 1 in 10 Mounjaro users and is usually mild. Management strategies include eating smaller, more frequent meals, avoiding acidic or spicy foods, staying upright after eating, and using over-the-counter antacids like omeprazole if needed. If you have a history of severe GERD or Barrett's oesophagus, discuss this with your prescriber before starting. Most people find it resolves or improves as their body adjusts to the medication over several weeks.
Ready to take control of your weight loss journey?
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