Alexandra
↓ 29.5 kg“The first few weeks were rough and they didn't just tell me to push through. They brought the dose down and checked in every week until it settled.”
PPRX member · weight-loss programme · 12 months
Free BMI check · 30 seconds
BMI Calculator
Your BMI
Enter your details to calculate your BMI.
Real patients
Lose weight, gain
It's more than the number on the scales — in their own words.
Adam
↓ 41.3 kg“Ordered on the Monday, at my door Wednesday morning, every single month. Not once have I had to chase them or ration what I had left.”
PPRX member · weight-loss programme · 13 months
Rebecca
↓ 28.4 kg“I messaged at half nine on a Sunday expecting nothing till Monday. Someone came back within the hour — and it was an actual pharmacist, not a script.”
PPRX member · weight-loss programme · 12 months
Megan
↓ 30.8 kg“Around month four I stalled completely and I was ready to pack it in. They explained why it happens, held the dose steady, and it started shifting again — nobody panicked except me.”
PPRX member · weight-loss programme · 14 months
Weight-loss medication works alongside diet and activity — individual results vary
What to expect
How long until you see results?
In clinical trials, GLP-1 treatment produced steady, compounding weight loss over the first year — steepest at the start, settling as you approach your new weight. Here's the honest shape of it.
Check your eligibility
Free consultation · Subscribe or order one-off · Cancel anytime
4.9
Rated Excellent on Trustpilot.
107 verified patient reviews
“They're amazing. No stress. Very helpful. And very professional.”
“Very quick order and easy delivery.”
“Quick and easy to place the order and very fast processing and delivery. Used the service to get a prescription whilst on holiday as I extended my trip and was a straightforward process.”
“After being rejected by other online pharmacies, PPRX fulfilled my prescription and delivered next day. Excellent comms. Very well packaged. Thanks.”
BMI, answeredYour BMI questions,
Your BMI questions,
answered.
What BMI can tell you, what it can't, and where the thresholds for treatment actually sit. A clinician answers the rest, by name.
❏Seven honest answers
How is BMI calculated?
BMI (body mass index) is your weight in kilograms divided by your height in metres squared. Someone who is 1.70 m and 95 kg has a BMI of 95 ÷ (1.70 × 1.70) = 32.9. Our calculator does the conversion for you — enter your weight in kilograms, pounds or stone, and your height in centimetres or feet and inches.
What do the BMI categories mean?
The NHS bands are: under 18.5 underweight, 18.5–24.9 healthy weight, 25–29.9 overweight, and 30+ obese. They're a population-level screening tool — a starting point for a clinical conversation, not a diagnosis.
What are the limits of BMI?
BMI can't tell muscle from fat, so very muscular people can score 'overweight' while carrying little fat. NICE also advises lower thresholds for people from South Asian, Chinese, other Asian, Middle Eastern, Black African or African-Caribbean backgrounds, whose health risks rise at lower BMIs. That's why a prescriber reviews the whole picture, not just the number.
What BMI do I need for weight-loss medication?
The licensed criteria are a BMI of 30 or higher, or 27 or higher alongside a weight-related condition such as hypertension, type 2 diabetes or sleep apnoea. Below those thresholds our prescribers won't issue a GLP-1 prescription — the consultation confirms suitability either way.
Is BMI different for men and women?
The calculation and NHS categories are the same for adult men and women. Body composition differs between sexes, which is one of BMI's known limitations — another reason it's used as a screen rather than a verdict.
How much weight could I lose on Mounjaro or Wegovy?
Trial averages range from around 15% of body weight with semaglutide (Wegovy, STEP 1) to around 20% with tirzepatide (Mounjaro, SURMOUNT-1) over a year or more, alongside diet and activity. Individual results vary — some lose more, some less.
What if my BMI is below 27?
We won't prescribe weight-loss medication — it isn't licensed, or healthy, below the thresholds. If you'd still like structured support, our coaching plans (meal planning and training) are available without a prescription, and your GP is the right first step if your weight worries you in either direction.
References
- 1.Wilding JPH, et al. Once-Weekly Semaglutide in Adults with Overweight or Obesity (STEP 1). New England Journal of Medicine, 2021. nejm.org/doi/full/10.1056/NEJMoa2032183
- 2.Jastreboff AM, et al. Tirzepatide Once Weekly for the Treatment of Obesity (SURMOUNT-1). New England Journal of Medicine, 2022. nejm.org/doi/full/10.1056/NEJMoa2206038
- 3.NHS — Body mass index (BMI): about, categories and limitations. nhs.uk/health-assessment-tools/calculate-your-body-mass-index/
Weight-loss medicines are prescription-only. Suitability is always confirmed by a UK-registered prescriber.
Ready when you areStart your
Start your
free consultation.
Three minutes of your time, reviewed by a UK-registered prescriber. No commitment, no charge for the consultation — and if treatment is approved, free next-day delivery to your door.
★ 4.9 Trustpilot·GPhC #9012740·Free next-day delivery·No subscription traps