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
Free tracker included with every download this week
7.5 Mg Mounjaro Side Effects — Costs and UK Access
At 7.5 mg, Mounjaro (tirzepatide) is in the dose escalation phase, where side effects may be more noticeable than at the starting 2.5 mg dose. Understanding what to expect — and how much this dose costs in the UK — helps you make an informed decision. This guide covers common side effects at 7.5 mg, private prescription costs, NHS access routes, and what the online assessment process involves. Use our GLP-1 weight loss calculator to explore potential outcomes at different doses, and check your BMI using our free BMI calculator to understand your eligibility.
10,000+ calculations today · NHS-aligned thresholds · 100% free
Calculate Your BMI Instantly
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.
Common Side Effects at 7.5 Mg and UK Prescription Costs
At 7.5 mg Mounjaro, most people experience the escalation phase of side effects. The most commonly reported include nausea, diarrhoea, vomiting, and constipation — these typically peak during the first week of a new dose and often subside within 5–7 days as your body adjusts. Less common but notable side effects include indigestion, fatigue, dizziness, and injection site reactions (redness or bruising where you inject).
In the UK private market, a single KwikPen containing four 7.5 mg doses (one month's supply) typically costs between £180–£240, depending on the provider and whether you're a new or returning customer. Some services offer discounts for three-month bundles, bringing the per-dose cost down. This is substantially less than the NHS cost per dose (which exceeds £300), but private treatment requires you to pay upfront and manage your own prescriptions, whereas NHS treatment is free at the point of use for eligible patients.
- Nausea is very common but usually manageable with small, frequent meals
- Stomach pain should be monitored — severe pain requires urgent GP assessment
- Hair loss (alopecia) has been reported in some users but is usually reversible after stopping
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 Access vs Private Prescription Routes
In the UK, you can access Mounjaro (tirzepatide) through two main routes. The NHS route requires referral from your GP to a tier 3 specialist weight management service. Once referred, you'll undergo a multidisciplinary assessment and, if approved, can receive Mounjaro free on prescription. However, NHS waiting lists are substantial in many regions — some services have waits of 18 months or longer, and not all integrated care boards (ICBs) currently fund tirzepatide.
The private route is faster: you complete an online consultation with a UK-licensed prescriber through a GPhC-registered pharmacy, receive a prescription if approved, and the medication is delivered to your home. The entire process typically takes 2–3 days. No referral is needed, and you don't need to meet NHS thresholds, though the prescriber will still assess your eligibility based on BMI and health conditions. Track your progress with our free progress tracker once you start treatment.
- 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.
Is 7.5 mg Mounjaro more expensive than lower doses in the UK?
No — all doses are contained in the same KwikPen with four doses per month. A pen containing 7.5 mg costs the same as a pen containing 5 mg or 10 mg (typically £180–£240 privately). You pay per pen, not per dose. NHS treatment is free once approved, regardless of dose.
What happens if I can't tolerate side effects at 7.5 mg?
You can pause escalation or reduce back to your previous dose. Always discuss this with your prescriber before making changes. Many people find side effects reduce after 5–7 days on a new dose. Your GP or private prescriber can offer anti-nausea strategies and dietary advice to manage symptoms.
Can I get 7.5 mg Mounjaro on the NHS immediately?
No — NHS access requires referral to a specialist weight management service and can involve significant waiting times (weeks to months depending on your region). Private prescription is faster (typically 2–3 days) but costs apply. Both routes require clinical assessment and you must meet BMI and health condition eligibility criteria.
How long can I stay on 7.5 mg Mounjaro?
You can remain on 7.5 mg indefinitely if it works well for you and side effects are manageable. Dose escalation is optional — not mandatory. Your prescriber will help you find the effective dose with the best side effect profile for you. Many people maintain weight loss at 5–7.5 mg without escalating to maximum dose.
What's the difference between Mounjaro and Wegovy at this dose level?
Mounjaro is a dual GIP and GLP-1 agonist; Wegovy (semaglutide) is GLP-1 only. At 7.5 mg Mounjaro, clinical trials showed approximately 19.5% average weight loss. Wegovy reaches maximum 2.4 mg with approximately clinically studied weight loss. Both require prescription and clinical assessment. Individual results vary considerably.
Ready to take control of your weight loss journey?
Start with a free BMI check, explore your GLP-1 options, or begin tracking your progress today. No sign-up. No cost. Just results.