How Long Does It Take For Mounjaro To Work?

If you’ve just gotten your Mounjaro prescription, you’re probably wondering when you’ll start seeing changes on the scale. Or if you’re still deciding if Mounjaro is right for you, you might be trying to work out what you can expect by being on it.

Mounjaro is a breakthrough medicine for medical weight loss, helping many people achieve significant results. While everyone’s body responds differently, knowing what to expect week by week can help you stay motivated and on track.

What is Mounjaro?

Mounjaro (tirzepatide) is a once-weekly injectable medication that works with your body’s natural hormones to reduce appetite and help you feel full longer. It’s part of a class of new weight loss medications called GLP-1/GIP receptor agonists, which treat obesity and type 2 diabetes.

How long does it take for Mounjaro to start working?

Mounjaro starts working within hours of your first injection by adjusting your body’s appetite and metabolism. However, noticeable changes may take several days or weeks as your body adapts to the medication.

Clinical studies show that Mounjaro can help users lose up to 22.5% of their starting body weight when using the maximum dose of 15 mg after 72 weeks of treatment. For example, someone beginning at 113kg could lose approximately 25.4kg. 

You will start on 2.5mg, and your doctor or pharmacist will gradually increase your dose over several months to maximise your results while minimising side effects. This gradual adjustment allows your body to settle into a sustainable pattern of weight loss.

Week-by-Week Expected Results Using Mounjaro

We have put together a guide of what to expect from using Mounjaro based on findings from the Surmount 1 clinical trials. We’ve also taken feedback from Mounjaro reviews from real users to make sure this matches with most users’ experiences.

Everyone’s body responds differently to using Mounjaro for weight loss, so your weight loss journey may vary from what we describe.

Weeks 1-4

Recommended Dosage: 2.5mg

Weight Loss: People tend to lose up to 4% of their body weight by week 4. Don’t be disheartened if you do not see results in week 1.

What to Expect: The biggest change in the first month is that many patients report feeling satisfied with smaller portions and not feeling hungry throughout the day. It’s early to notice any physical differences at this point.

Side Effects: The most common initial side effects include mild nausea, reduced appetite, and digestive changes. These tend to improve as your body gets used to the medication.

Feedback from Mounjaro Reviews: 

• “I’m in my second week, and I think the pen is great, easy to use, has no side effects, and has stopped my constant need to snack.”
• “Fantastic. Lost almost a stone in 4 weeks. Highly recommend. No side effects.”

Tips:

• Even if you are feeling queasy, make sure you keep drinking enough water. Dehydration will make your side effects worse and will put a strain on your body.
• Try keeping a food diary where you are really honest with yourself about what you are eating. This might help spot if you’re having high-fat foods or sugary snacks that slow down your weight loss journey. Snacking can be due to a habit rather than being hungry.
• Don’t be tempted to skip meals to speed up weight loss. Your body needs the right foods to fuel it, and you can cause nutritional deficiencies.
• Set yourself up with an exercise plan to support your weight loss.

Weeks 5-8

Recommended Dosage: 5mg

Weight Loss: By this stage, many patients have lost approximately 5-6% of their body weight.

What to Expect: Your clothes might begin feeling looser, and you should feel fuller for longer, which will help you avoid snacking between meals.

Side Effects: While the increase in dose might temporarily bring back some side effects, these usually go away more quickly than in the first month. If your side effects are severe, your doctor or pharmacist may keep you on a lower dose until they subside.

Feedback from Mounjaro Reviews: 

• “I lost 1 stone 5 lbs over 2 months, felt a little bit of nausea but nothing I couldn’t deal with! Very pleased with the results!”

Tip: 

• Get into the routine of meal planning so you have a variety of food throughout the week and get the nutrition you need. Finding new weight loss recipes and meal plans may give you some inspiration for tasty, healthy foods you can try. 
• Try to do your food shop weekly and only buy what you need for your meal plan. This will help on days when you’re feeling low energy and tempted by unhealthy foods.
• Remember, you must eat, even if you have little appetite or feel nauseous. Try eating plain foods that are easy to swallow. 

Weeks 9-12

Recommended Dosage: 7.5mg

Weight Loss: By the third month, most people establish a more predictable weight loss pattern, with total losses often reaching 8-9% of your starting body weight.

What to Expect: This period often marks a milestone in your treatment, as many patients report increased energy levels and more consistent appetite control.

Side Effects: Side effects usually become milder during this phase, though you might notice brief changes when starting the new dose. Most patients find they’re adjusting well to the medication by this point, making it easier to focus on their weight loss journey.

Feedback from Mounjaro Reviews: 

• “This product is fab. I have lost 22 pounds in 11 weeks with barely any side effects. I am so thankful, as I have tried and failed to lose weight before to no avail.”
• “I have had a great experience using this product. I am 3 months in and 21lbs down. I have tried everything possible to lose some weight and only ever lose a couple of lbs. Having an underactive thyroid gave me huge challenges, but this has changed everything. I’ve never lost this much weight and I feel so much better in myself already.”

Tip: 

• By now, you’ll be losing weight and feeling proud of yourself. Try not to weigh yourself too often, as this can be disheartening. Weight fluctuates throughout the day and across the week, depending on your water retention and hormone levels.

Weeks 13-16

Recommended Dosage: 10mg

Weight Loss: As you begin taking the 10 mg dose, you’ll likely notice more significant changes in your weight and overall well-being. Most patients have lost approximately 9-12% of their body weight by this stage in their treatment.

What to Expect: You will probably notice significant changes in how your clothes fit, and your energy levels will have risen.

Side Effects: Side effects are usually stable at this point, though some people may experience temporary digestive changes like constipation or nausea with the dose increase.

Feedback from Mounjaro Reviews: 

• “In my experience, it has effectively reduced any food noise and hunger. No side effects whatsoever…Over 14 weeks, I’ve lost 2stone. I started 13st 6lbs, now 11stone 6lbs, which is 2lbs per week on average. Thank you, Click2Pharmacy.”
• “It works. Zero appetite, lower blood sugars, and digestive discomfort if you try to eat high-carb/fatty/fried food. The side effects are minimal if you stick to a bland, simple diet, nutrient-dense foods and protein, and lots of water as recommended.”

Tip: 

• If you have started an exercise routine alongside Mounjaro, you might gain muscle as you lose weight. Judging your weight loss solely by the scales can be confusing, so think about how your clothes fit and how toned you look. 

Weeks 17-20

Recommended Dosage: 12.5mg

Weight Loss: Many people see total losses of roughly 10-13% by this stage. 

What to Expect: Weight loss typically continues at a steady pace. By this point in treatment, most people have developed consistent eating patterns and feel confident managing their medication routine. 

Side Effects: Many people have adapted well to the medication by weeks 17-20, with minimal new side effects from dose increases.

Feedback from Mounjaro Reviews: 

• “Life-changing product for the better. I’ve never felt so good. Easy to use, I’m never hungry and do not crave anything. Well worth it. It costs much less than I’m saving by not buying treats, wine, and comfort food. I am very happy.”

Tip: 

• Celebrate achieving milestones along the way, like hitting your exercise goals or being able to do things in daily life, like longer walks without joint pain.

Weeks 21 Onwards

Recommended Dosage: 15mg

Weight Loss: This is the maintenance phase where you’ll reach Mounjaro’s full potential. By week 72, you could lose approximately 22.5% of your starting body weight, depending on the strength of the dose you take.

Side Effects: Side effects are usually minimal at this stage, as your body has fully adjusted to the medication.

Feedback from Mounjaro Reviews: 

• “I am in 7 months Mounjaro and do not have any regret. Losing 20 kg is a slow process.”

Tip: 

• When you reach your target weight, don’t stop taking Mounjaro. Speak to your doctor or pharmacist about your next steps.

Increasing Your Mounjaro Dosage

Following the recommended Mounjaro treatment plan, most people reach the maximum dose of 15mg by week 21. The dosing schedule can be extended over more weeks, but you cannot skip dosage strengths or reduce the four-week window between increases, even if you feel ready for a higher dose.

There’s no rush to reach the higher doses of Mounjaro. The most successful long-term outcomes often come from finding the right balance between effectiveness and tolerability, even if that means taking a slower approach to dose increases. 

Your GP or pharmacist may recommend staying on a lower dose longer in certain situations, such as during periods of illness or stress, if you’re experiencing significant side effects, or when you’re achieving good results at your current dose.

Things That Can Affect How Quickly You Lose Weight With Mounjaro

Your weight loss journey with Mounjaro is unique to you. While clinical trials show impressive results, there are several personal factors that influence how quickly and effectively the medication works for you:

Starting Weight and BMI

Your initial weight and Body Mass Index (BMI) affect how quickly you might lose weight on Mounjaro. If you’re starting at a higher weight, you might notice bigger changes on the scale in the early weeks. If you’re closer to your goal weight, you might lose weight more slowly. Both scenarios are completely normal.

Your Health Background

Your overall health affects how your body responds to Mounjaro. If you have other health conditions or take other medications, this might also affect your weight loss journey.

Always tell your GP or pharmacist about any medications you take, including vitamins and supplements. This helps them make sure you’re getting the safest and most effective treatment.

Your Daily Routine

While Mounjaro helps reduce your appetite and makes you feel fuller for longer, your daily habits and your commitment to your lifestyle changes still matter. Your diet and exercise, how well you sleep, and how you handle stress all work together with Mounjaro to influence your weight loss.

Natural Body Changes

Your weight can naturally go up and down due to things like hormones, water retention, or stress. These normal fluctuations don’t mean Mounjaro isn’t working – they’re just part of your body’s natural rhythm. Being aware of your natural body changes can help you stay motivated when the number on the scale varies from week to week.

Tips to Get the Best Results When Taking Mounjaro

Making the most of your Mounjaro treatment means combining the medication with healthy lifestyle choices:

Eating Well on Mounjaro

Mounjaro helps control your appetite, but eating the right foods is still important. Try to include plenty of protein in your diet, like chicken, fish, eggs, or legumes, as these foods help you feel satisfied and maintain muscle while losing weight. Make sure you add plenty of vegetables to your meals for nutrients and fibre.

You might find you get full more quickly on Mounjaro. Instead of three big meals, try eating smaller amounts more often throughout the day so you don’t feel too full or uncomfortable.

Getting Active

Moving more helps boost weight loss results. You don’t need to start training for a marathon, but even regular short walks and gradually doing more as your energy levels improve will make a difference. Aim for about 30 minutes of activity on most days, but listen to your body – if you’re feeling tired or unwell, it’s okay to take it easier.

Keeping Track of Your Progress

It’s helpful to keep notes about how you’re feeling, including things like your weight changes, any side effects, and your energy levels. When you speak to your doctor or pharmacist about renewing or altering your dose, this information helps them make good decisions about your treatment.

Support Matters

Having support makes a big difference to your success. It’s always easier to eat healthily or get active when your close friends or family members encourage you and join you in healthy habits. 

Your healthcare team is there to support you, too – don’t hesitate to ask questions or raise concerns with your doctor or pharmacist.

Start Mounjaro and Lose Weight with Click2Pharmacy

Starting your weight loss journey with Mounjaro is an exciting step forward, and our online weight loss clinic makes it simple to get started. Our experienced pharmacists will provide professional support as you work through the dosage schedule.

Ready to take the first step? Complete your consultation with Click2Pharmacy today. Together, we’ll help you achieve your weight loss goals.