How Much Weight Can You Lose on Mounjaro in 3 Months?

Mounjaro is a weekly self-injectable weight loss pen that contains the active ingredient tirzepatide. It works by reducing your appetite, suppressing cravings, and regulating blood sugar levels.

If you have just started Mounjaro treatment or are a few weeks in, you’re probably wondering how much weight you can expect to lose in the first three months. Here, we examine some of the data to provide a clearer understanding of what you can expect from your weight loss journey with Mounjaro.

How does Mounjaro work for weight loss?

Mounjaro works by mimicking two digestive hormones. They are:

• Gastric inhibitory polypeptide (GIP)
• Glucagon-like peptide-1 (GLP-1)

These two hormones are the primary incretin hormones released by the intestines in response to the ingestion of sugar, triggering the release of insulin. The active ingredient in Mounjaro, tirzepatide, works in several ways to promote weight loss.

Source: Eli Lilly (2023)

How much weight can you lose on Mounjaro in 3 months?

At the maintenance dose of Mounjaro, after 3 months, you can expect to lose an average of 9% of your body weight. However, the exact amount of weight you can lose with Mounjaro will depend on several factors, including your lifestyle and the dosage of Mounjaro.

A study published in the New England Journal of Medicine in 2022 investigated the average weight loss achieved with three different doses of Mounjaro over 72 weeks. The results for the first three months are summarised in the table below:

Further clinical trials have shown that the average weight loss after one month of Mounjaro treatment is 4% and 6% after two months.

Mounjaro long-term weight loss expectations

Studies show that people who use Mounjaro for over one year can lose up to 20% of their body weight when using the highest Mounjaro dose of 15 mg per week. So, someone who weighs 160 kg could lose 32 kg over a 72-week period.

The SURMOUNT-4 study was conducted over 88 weeks and involved 670 overweight individuals. It demonstrated that the average weight loss using Mounjaro during 88 weeks was just over 25%.

Mounjaro dosage schedule

The usual Mounjaro dosage schedule is as follows:

The starting dose is 2.5 mg once a week for 4 months. Then, your clinician will increase your dose to 5 mg a week for 4 weeks, and so on, until you reach the 15 mg per week maintenance dose.

Will you lose more weight on higher Mounjaro doses?

Research indicates that higher doses of Mounjaro result in a greater average weight loss. For example, after 72 weeks, the average weight loss across 3 tirzepatide doses was:

• 5 mg/week
• 10 mg/week
• 15 mg/week

The maximum available dose of Mounjaro is 15 mg per week. Your clinician will tell you when to increase your dose and by how much. Although the most weight loss is typically seen at the maximum maintenance dose, when you reach this dose will depend on how well your body reacts to the medication and whether you experience any side effects.

You can find out more about Mounjaro side effects by reading our blog: ‘How long do Mounjaro side effects last?’

How to increase Mounjaro’s effectiveness

Mounjaro works best when used in conjunction with a diet and exercise plan. It is essential to maintain a healthy, balanced diet when self-injecting Mounjaro injections on a weekly basis. Your diet should consist of:

• fruit
• vegetables
• wholegrains
• lean protein
• low-fat dairy

However, there are some foods you should avoid when using Mounjaro weight loss injections, such as:

• sugary foods
• fried or processed foods
• high GI foods
• refined carbohydrates
• alcohol

Exercise is also an important aspect of the weight loss journey with Mounjaro. Some tips include:

• move for 3 minutes every half an hour
• incorporate daily chores into your activity routine, such as cleaning, gardening, ironing and so on
• take the dog for a walk or spend a few minutes playing with your children or grandchildren to get your heart pumping
• call a friend and invite them on a walk, or put your headphones on, crank up the tunes and start with a short walk, building up to longer, faster walks

Which is better: Mounjaro or Wegovy?

The weight loss injection most suitable for you will depend on several factors, including how well you react to the medication, whether you experience side effects, and your medical history.

At Prescription Doctor, we offer several weight loss treatments:

• Wegovy
• MySimba
• Alli (orlistat)

Summary

Embarking on a weight loss journey is a commitment. When you use Mounjaro weight loss injections, research shows that you can expect to lose between 8 and 9% of your starting body weight. Mounjaro injections can be used long-term, with some studies showing that at the highest dose, it’s possible to lose one-quarter of your body weight.

If you think Mounjaro may be a suitable weight loss option for you, you can buy Mounjaro online from Prescription Doctor. Start your online consultation with one of our clinicians today.

Authored By

Leanne Edermaniger

Medical Content Writer

Leanne is a science and health content writer focusing on human health and biology while utilising her solid academic background.

Published on: 06/08/2024

Reviewed By

Mohamed Imran Lakhi

MPharm - Lead Pharmacist

Imran Lakhi is the superintendent pharmacist and founder at Prescription Doctor. He has been at the core of our team.

Reviewed on: 05/06/2025