Free Tool

Is your Mounjaro or Wegovy dose working?

Answer seven questions about the last few weeks and see how your current dose is performing, so you walk into your review knowing what to ask.

  • Compared against trial data
  • Safety questions come first
  • Every result explained in plain English
1

Your details

Every field is required

Medication

The Wegovy checker is not ready yet. The scoring behind this tool is built on tirzepatide trial data, which does not carry across to semaglutide. We would rather leave it out than guess at the numbers, so Wegovy is not selectable for now.

Current dose

Select the dose the patient is taking now.

Weight
Baseline weight
kg
Current weight
kg
wks
%
Side effects
Hours of appetite control each day

0h

of 24 hours on Monday

0 of 168 hours

About 0h a day this week

Poor
2

Recommendation

No assessment yet

Enter the patient's details, then press Review this dose.

How the checker works

Weight loss on a GLP-1 medication is not steady, and a slow month does not always mean the dose is wrong. The checker compares what has actually happened against what the clinical trials saw at your dose, then explains which parts of your answer moved the result.

Safety questions come first

Four questions are checked before anything is scored. If any one of them applies, it decides the outcome on its own — because in those situations the numbers cannot be read fairly.

  1. 1Are you already at the highest dose?Mounjaro goes up to 15 mg and Wegovy to 2.4 mg. At the top of the range there is no increase left to make, so the checker stops there.
  2. 2Are your side effects severe?Severe effects mean the checker suggests speaking to your prescriber about coming down rather than going up, whatever the weight change shows.
  3. 3Have you taken at least 60% of your doses?Below that, a slow result says more about missed injections than about the dose itself, so there is nothing meaningful to measure.
  4. 4Have you been on this dose for 4 weeks or more?GLP-1 medication takes weeks to show its full effect. Judging it sooner tends to prompt a change that was never needed.

What the checker measures

  1. 1Your weight change becomes a rateThe weight you have lost is divided by the number of weeks you have been on this dose, giving a change per week that can be compared with what the trials saw.
  2. 2The expectation is adjusted for missed dosesTrial figures assume every dose is taken. If you have taken 80% of yours, the expectation is scaled to 80% before anything is compared — otherwise the dose is blamed for missed injections.
  3. 3Appetite control is measured across the weekThe hours a day you felt your appetite was under control are added up and measured against the 168 hours in a week. Under half often means the medication is wearing off before the next injection.
  4. 4Everything is scored, and the score decidesEach factor adds or removes points. A high score suggests your response is below what the dose should deliver; a score near zero suggests it is working as expected.

Expected weight loss by dose

These are the average rates recorded in the SURMOUNT trials of tirzepatide, the medicine in Mounjaro. They are averages across thousands of people — an individual week can look nothing like them, which is why the checker looks at several weeks at once.

Mounjaro doseTypical weekly lossUsual range
2.5 mg0.4 kg0.250.6 kg
5 mg0.5 kg0.30.7 kg
7.5 mg0.55 kg0.350.75 kg
10 mg0.625 kg0.40.85 kg
12.5 mg0.675 kg0.450.9 kg
15 mg0.725 kg0.50.95 kg

Medical disclaimer

Only your prescriber can change your dose. This tool helps you describe how you are getting on, so your review is a better conversation. It does not give medical advice — always read the patient information leaflet that comes in your medication box, and speak to your prescriber or pharmacist about anything that concerns you.

Where these numbers come from

Built by the CoolDose teamLast updated

  • The expected weight-loss rates. The SURMOUNT programme for tirzepatide, the medicine in Mounjaro. Jastreboff AM, Aronne LJ, Ahmad NN, et al. “Tirzepatide Once Weekly for the Treatment of Obesity.” New England Journal of Medicine, 2022;387(3):205–216. PubMed

  • Which doses the trial covered. SURMOUNT-1 reported the 5 mg, 10 mg and 15 mg maintenance doses over 72 weeks. The rates this tool uses for 2.5 mg, 7.5 mg and 12.5 mg are interpolated between them rather than taken from the trial, and 2.5 mg is a titration step not intended to drive weight loss. Treat the figures for those three as a guide.

  • Why Wegovy is not available yet. Those rates are tirzepatide rates. Semaglutide was studied in a separate programme and the two are not directly comparable, so there is nothing to carry across. Rather than score Wegovy against numbers we do not have, that path is switched off until the semaglutide figures are supplied.

  • The Mounjaro dose ladder and maximum dose. The Summary of Product Characteristics on the electronic medicines compendium. Always read the leaflet in your own box, which is the version that applies to you. medicines.org.uk

  • Tirzepatide in weight management. NICE technology appraisal TA1026, tirzepatide for managing overweight and obesity. nice.org.uk

  • Semaglutide in weight management. NICE technology appraisal TA875, semaglutide for managing overweight and obesity. nice.org.uk

  • What this tool is not. Only your prescriber can change your dose. This is a way to describe how you have been getting on so your review is a better conversation, not a recommendation to act on by yourself. nhs.uk

About this tool

Common questions

It applies a fixed scoring algorithm to a patient's response at their current dose and suggests whether to increase, maintain or decrease. It supports a pharmacist's judgement — it does not replace it.

The SURMOUNT programme for tirzepatide (Mounjaro). Each dose has a target kg-per-week figure, which is then adjusted for the patient's adherence before being compared with their actual rate.

Four safety checks run first: already at the maximum dose, severe side effects, adherence under 60%, or fewer than four weeks at the current dose. Any one of them decides the outcome on its own, because the response cannot be fairly assessed.

No. Only your prescriber can change your dose. This is a way to describe how the last few weeks have actually gone — weight change, side effects, appetite control — so your next review is a better conversation. Take the result with you rather than acting on it, and read the patient information leaflet in your medication box, which is the version that applies to you.

The hours of appetite control reported for each of the seven days are summed and divided by 168, the number of hours in a week.