Do Weight Loss Jabs Work?

Both Mounjaro and Wegovy are once-weekly injectable medicines that work by acting on hormone receptors involved in appetite and blood-sugar regulation. Wegovy contains semaglutide, a GLP-1 receptor agonist; Mounjaro contains tirzepatide, which acts on both GLP-1 and GIP receptors. Together, these mechanisms are commonly described as reducing appetite, increasing the sense of fullness after eating, and slowing the rate at which the stomach empties — an effect that often lessens over time.

Many people on these medicines report a noticeable reduction in "food noise" — the persistent preoccupation with food that can make managing intake difficult. This is not the same as willpower; it reflects a direct pharmacological effect on appetite-signalling pathways. For a more detailed look at the underlying science, see our guide on how weight loss jabs work.

Do weight loss jabs work for everyone?

Not necessarily. Results depend on a range of individual factors — including starting weight, metabolic health, diet, activity levels, how the body responds to the medicine, and how consistently the prescribed regimen is followed. Some people experience substantial changes; others see more modest results. Suitability and expected outcomes are something only your prescriber or doctor can assess for your specific situation. These medicines are also typically used alongside changes to diet and physical activity, not instead of them.

It is also worth noting that these are prescription-only medicines — which means they have been assessed as appropriate for a specific individual by a qualified clinician. If you have questions about whether the medicine is working as expected for you, the right person to ask is your prescriber. You can read a broader overview on our weight loss injections guide, or explore practical information about weight loss jabs more generally.

One of the most useful things you can do while on a weight loss injection is build a clear, consistent picture of what is happening in your body over time — because progress is rarely just about the number on the scale.

GLP Trackr's weight and body tracking feature lets you log your weight regularly and view it as a chart, so you can see trends across weeks rather than reacting to day-to-day fluctuations. Many people find this perspective genuinely reassuring — a week that looks flat in isolation often sits within a clear downward trend when you zoom out.

Alongside weight, the app's daily check-in captures mood, energy, sleep, food noise, and water intake in about 30 seconds. Over time, these data points feed into insights that can help you understand what is actually moving your results — and what might be getting in the way. If you want to bring a clear summary to your next prescriber appointment, the doctor report feature pulls your logged data together in one place.

GLP Trackr also keeps a log of every injection — dose, date, and site — so you always have an accurate record of your treatment history. For more on how access to these medicines typically works, see our page on weight loss jabs, pharmacies, and prescriptions.

Always follow the guidance of your prescriber or doctor — they know your full medical history and are best placed to assess how your treatment is progressing. If anything feels unexpected or worrying, contact your healthcare professional promptly rather than adjusting anything on your own.

Start building a clearer picture of your journey today — GLP Trackr is free to try for 7 days on the App Store and Google Play.