Starting a new medication often comes with one big question: when will I notice a difference?
If you've recently started Mounjaro, you may be wondering when it will begin affecting your appetite or when you'll start seeing changes on the scales.
The answer is different for everyone.
Mounjaro starts working in your body after your first injection, but the changes you notice can vary from one person to another. Your dose is increased gradually over several weeks to help your body adjust to treatment, so the full effects aren't expected immediately.
Here's what you can realistically expect:
What happens after your first injection?
After you inject Mounjaro, the medicine is gradually absorbed into your bloodstream and begins activating GLP-1 and GIP receptors.
These receptors are involved in regulating appetite and food intake.
Although the medicine starts working after your first dose, the changes you notice may be gradual. Some people first notice they feel full sooner during meals, while others find they think about food less often or snack less between meals.
Everyone's experience is different.
Why doesn't everyone notice changes at the same time?
There isn't a single timeline that applies to everyone.
How quickly you notice changes can depend on several factors, including:
- the dose you're currently taking
- your body's response to treatment
- your eating habits
- your activity level
Treatment also starts on a lower dose before increasing gradually, according to the licensed dosing schedule. This approach helps reduce the likelihood of gastrointestinal side-effects while allowing your body to adjust.
Good to know
Don't compare your progress with someone else's. Weight loss and appetite changes vary from person to person.
When does weight loss begin?
Some people notice changes in their appetite before they notice changes in their weight.
That's because Mounjaro supports weight loss by helping to regulate appetite and reduce energy intake. Over time, eating fewer calories than your body uses can lead to weight loss.
The amount of weight someone loses, and how quickly they lose it, varies between individuals. Your prescriber will review your progress throughout treatment.
What if you haven't noticed any difference?
It can be frustrating if you expected the medication to have an immediate effect.
Not noticing a dramatic change straight away doesn't necessarily mean the treatment isn't working.
Instead of focusing only on your weight, think about whether you've noticed other changes, such as:
Signs worth looking out for
| Sign | When it's often noticed |
|---|---|
| Feeling full sooner | Often one of the first changes |
| Eating smaller portions | Often noticed early on |
| Snacking less often | Often noticed early on |
| Finding healthy eating easier | May build gradually |
| Changes on the scales | Can take longer to show |
If you're concerned that your treatment isn't having the expected effect, speak to your prescriber rather than changing your dose yourself.
Should you increase your dose sooner?
No.
Your dosing schedule increases gradually, step by step, so your body has time to adjust.
Increasing your dose earlier than prescribed isn't recommended and may increase the risk of side-effects.
Always follow the treatment plan provided by your prescriber.
Frequently asked questions
Does Mounjaro work after the first injection?
Yes. Mounjaro begins working after the treatment starts, although the changes you notice may develop gradually.
Why haven't I lost weight yet?
Weight loss varies from person to person. Some people notice changes in appetite before they notice changes in their weight.
Will increasing my dose make it work faster?
Only increase your dose according to the plan agreed with your prescriber. Don't change your treatment yourself.
Is it normal for progress to vary?
Yes. Everyone responds differently to treatment, so progress isn't always the same from one person to another.
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Thinking about Mounjaro?
If you're considering prescription weight loss treatment, complete our online consultation. One of our prescribers will assess whether Mounjaro is suitable for you. If prescribed, it should always be used alongside a reduced-calorie diet and increased physical activity.
