Why Am I Not Losing Weight on Mounjaro?

If you’ve been taking Mounjaro^® (tirzepatide) and you’re not getting the weight loss results you want, you probably have questions. Is it that particular medication? Are you taking it correctly? Is there something else you should be doing differently?

Take a deep breath, and know that there are several reasonable explanations why you aren’t losing the weight you’d hoped to and plenty of solutions that can help support your weight loss journey.

Some examples: You may not be in a calorie deficit or you may have hit a weight loss plateau. Maybe you need a higher dose, want to try a different medication, or could adopt additional healthy habits to help you reach your goal. Keep reading to see what might be holding you back from hitting your weight loss goals — and what you can do about it.

“Results may vary” may feel like a part of every medication advertisement. That’s because individuals respond to drugs differently. Mounjaro and weight loss medications are no exception.

For context, Mounjaro is a brand name of the prescription medication tirzepatide, which is both a glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptor agonist. 

Tirzepatide helps control blood sugar and helps with weight loss by slowing down the time it takes for your stomach to empty so you feel fuller longer. The drug also works on the part of the brain that controls hunger and satiety by essentially tamping down your appetite. 

People on Mounjaro simply tend to eat less than they did before — an obvious, but important, factor for weight loss.

Mounjaro was approved by the Food & Drug Administration (FDA) to treat type 2 diabetes, but it’s sometimes prescribed off-label — for something that it’s not FDA approved for — to treat obesity and overweight. 

A 2024 study suggests that tirzepatide is generally safe and well-tolerated, while being an effective means of helping individuals lose weight and reduce their body mass index (BMI), a measure of healthy weight, overweight, and obesity.

Another version of tirzepatide called Zepbound^® was FDA-approved to treat obesity. The drugs have the same active ingredient, tirzepatide. Both Mounjaro and Zepbound are injected just under the skin once a week.

If you aren’t losing weight on Mounjaro, you may achieve better results using a similar medication that works a little differently in the body. Some of those drugs include:

• Ozempic^®, Wegovy^® (injectable semaglutide)

• Rybelsus^® (oral semaglutide)

• Saxenda^®, Victoza^® (liraglutide)

Some research suggests that Mounjaro may be more effective than Ozempic when it comes to weight loss in patients with type 2 diabetes.

If you aren’t getting the results you want with Mounjaro or you are experiencing side effects from that medication you’d rather avoid, talk with a healthcare provider about trying a different weight loss drug. 

Though these drugs all work in a similar way, the differences between them may make one more effective for you than another.

Though Mounjaro and similar drugs are effective for most people who try them, it’s possible that you may be in the minority of individuals who simply don’t respond well.

It’s not clear why certain people don’t respond as well as others to these weight loss drugs. In some cases, a stronger dose or a different drug is the key. For others, more rigorously following healthy lifestyle habits is the answer. And for others, the solution to sustained weight loss must be found without weight loss medications.

A stronger dose of Mounjaro may have a more significant effect. A 2022 study of 475 adults with type 2 diabetes found that individuals who took 15 mg of tirzepatide lost almost twice as much weight as those who took weekly 5 mg doses. In the study, patients were also taking insulin glargine, and the primary endpoint being researched was blood sugar control.

Doctors typically start their patients on the lowest dose of prescription medications that they expect to be effective, hoping to minimize the risk of side effects or other complications. But if you are able to tolerate Mounjaro at a low dose and would like to see if a stronger dose boosts your weight loss efforts, talk with your doctor about adjusting your prescription.

Mounjaro and weight loss medications aren’t cure-all solutions. Following a healthy eating program is a major factor in how successful you are on your weight loss journey. The medications may help suppress your appetite, but it’s critical that you adopt a balanced diet when you do eat.

A 2021 report on the most effective diets to support weight loss suggests that the most important factor is that you consume fewer calories than you use (as in, calorie deficit). The National Institutes of Health suggests trying to consume 500 fewer calories than you burn per day — a practice that may help you lose about a pound a week.

Researchers also recommend:

• Eating a nutrient-rich and filling breakfast

• Avoiding late-night snacking

• Adopting a dietary strategy that you can maintain over the long-term 

Need some ideas? The Mediterranean diet emphasizes vegetables, fruits, whole grains, lean proteins, and healthy fats (such as olive oil), while discouraging foods with added sugars that offer an abundance of carbohydrates and calories without healthy nutrients.

Prioritizing lean protein is especially important for sustainable weight loss, as it makes you feel fuller longer and supports your efforts to sustain (and maybe even build) muscle mass while you lose body fat.

Just as it’s important to eat right while taking Mounjaro, it’s also helpful to boost your physical activity level in order to lose weight and keep it off. Regular exercise, including a mix of cardio and strength training, should help you lose weight and maintain your weight loss.

If you haven’t started a regular exercise program, try to pick activities that you enjoy and will stick with, even on those days you’re not especially motivated. Working out with a friend or accountability partner can help make exercise more fun and help you stick with it.

Are you not losing weight at all or are you not losing as much as you thought you would? It’s not uncommon for people using Mounjaro to lose a lot of weight early and then hit a weight loss plateau, where the pounds come off more slowly.

Be realistic about your weight loss journey and understand that changes in your body weight aren’t always predictable or consistent. Changes in your hormones and other factors may also slow down your weight loss progress. Additionally, if you go off Mounjaro, you may experience weight gain.

If you’re unsure about what your weight loss journey will or should look like, talk with your healthcare provider. The more you know about what to expect, the better you’ll handle the inevitable ups and downs of using Mounjaro and weight loss medications.

Mounjaro and weight loss drugs are usually effective for most people. But if you’re not losing weight on Mounjaro, you may need a higher dose, or you may need to make other adjustments. You could also try taking a different medication to help you reach your weight loss goals.

No matter what medication you’re on, you should couple the prescription with impactful lifestyle changes, like reducing your caloric intake, engaging in more physical activity, and other healthy behaviors, such as getting quality sleep and managing your stress.

As with all prescription medications, if you are unsatisfied with how Mounjaro is working (or not working), talk openly with your healthcare provider. You may need to learn more about the medication in order to have a realistic perspective on how you’re responding to Mounjaro and whether any changes are necessary.

Hers can help connect you with a medical professional so you can get a doctor-trusted treatment plan tailored to your needs and experiences.