What happens when you stop taking Mounjaro?

Mounjaro (tirzepatide) is an injectable medication approved by the U.S. Food and Drug Administration (FDA) to improve blood sugar levels in adults with Type 2 diabetes. A notable side effect of this medication is weight loss, leading to off-label use as a treatment for obesity. Study participants taking Mounjaro lost up to 26% of their starting body weight over 84 weeks. (Also made by Eli Lilly, Zepbound contains the same active ingredient and is approved for chronic weight management.)

Mounjaro is typically prescribed for long-term use, but some people experience severe side effects of Mounjaro and can’t keep taking it. If your healthcare provider instructs you to discontinue Mounjaro, you may experience appetite changes, blood sugar issues, weight gain, and digestive upset. Here, learn more about what happens when you stop taking Mounjaro and how to discontinue this prescription medication.

Things that happen when you stop taking Mounjaro

Mounjaro mimics the action of glucagon-like peptide-1 (GLP-1) hormone as well as glucose-dependent insulinotropic polypeptide (GIP) produced by your body to stimulate the release of insulin, increase feelings of fullness, and increase the time it takes for food to travel out of your stomach. These effects help suppress appetite to spur weight loss and regulate blood sugar. Discontinuing the medication reverses the effects, which can cause a resurgence of hunger and dysregulated blood glucose—among other issues.

Appetite changes

Mounjaro reduces your appetite by slowing gastric emptying and promoting satiety. “When discontinuing Mounjaro, patients might experience a rebound in appetite,” says Alex Foxman, MD, the medical director of Achieve Health and Weight Loss. After all, part of the reason the medication works is because reduced hunger leads to better portion control.

Before you stop taking Mounjaro, make sure to have lean proteins, whole grains, fruits, and vegetables on hand. Sticking to the healthy diet recommended while taking Mounjaro can help limit increased hunger after stopping the medication. That also means trying not to overindulge in excess sugar, processed snacks, fried foods, and alcoholic beverages when your appetite rebounds.

Blood sugar issues

Mounjaro mimics the hormone glucagon to increase insulin secretion and decrease glucagon production, which can help lower blood sugar levels for people with Type 2 diabetes. Stopping the medication can cause your blood sugar levels to return to what they were before you started taking the medication.

Weight gain

If you take Mounjaro long-term, you may lose up to a quarter of your body weight. If you stop taking Mounjaro, you’ll likely regain at least some of that weight. A recent study on the effects of stopping Mounjaro after an intense 12-week cycle revealed some patients regained up to one-third of their lost weight. It’s crucial to continue the lifestyle changes you adopted when beginning Mounjaro, including diet modifications and increased exercise, as these tend to decrease the amount of weight gained after stopping the medication.

Digestive upset

Vomiting, constipation, and diarrhea are common side effects of Mounjaro that often subside once your body gets used to the medication. When you stop Mounjaro, you can expect a similar reaction, such as abdominal pain, nausea, and digestive issues as your body adjusts.

How long does Mounjaro stay in your system?

Mounjaro takes about 25 days to leave your system.

“Mounjaro has a half-life of approximately five days,” says Soma Mandal, MD, an internist at Summit Health Clinic in Berkeley Heights, New Jersey. “The half-life of a drug is the time it takes for half of the drug to be eliminated from the body. Generally, it takes about five half-lives for a drug to be almost completely eliminated from the body.”

After this point, you should no longer notice the changes that occurred when you first stopped taking Mounjaro.

When should you stop Mounjaro?

Mounjaro is approved for long-term use in patients with diabetes, but there are circumstances when stopping Mounjaro early may be recommended. Your provider may want to stop it in lieu of another medication if they are not seeing the results they’d like, but mainly, it will be if you experience severe side effects.

While GI side effects on Mounjaro and other GLP-1 medications (like Ozempic) are expected, they should be short-lived. If they are serious or not resolving, you should speak with your doctor about stopping the medication. Below are other serious adverse reactions that indicate a need to stop.

Allergic reaction

It is possible to have an allergic reaction to Mounjaro. Symptoms include:

• Rash or redness at the injection site
• Swelling of the face, lips, throat, or neck
• Difficulty breathing and anaphylaxis
• Sudden changes in blood sugar levels with a fever

Contact your healthcare provider if you notice any of these symptoms. Dial 911 if you have a severe reaction, especially any that cause trouble breathing.

RELATED: Mounjaro interactions to avoid

Acute pancreatitis

A rare side effect of tirzepatide is acute pancreatitis, which results from inflammation of the pancreas throughout treatment. If you begin to experience stomach pain, tenderness when touching your stomach, fever, vomiting, or rapid heartbeat, contact your healthcare provider. These are some of the most common signs and symptoms of early acute pancreatitis.

Acute gallbladder disease

Another small portion of patients experienced acute gallbladder disease (cholelithiasis, biliary cholic, and cholecystectomy) after taking tirzepatide. Gallbladder issues also include nausea and vomiting with pain in the upper-right side of the abdomen. Again, contact your healthcare provider if you experience any of these symptoms.

Endocrine complications

Tirzepatide can cause endocrine complications, including multiple endocrine neoplasia syndrome Type 2 (MEN2) and medullary thyroid carcinoma (MTC). These are types of cancers that arise from thyroid C-cell. Their warning signs may take the form of a lump along your neck, swelling, trouble swallowing, or vocal strain.

How to stop taking Mounjaro

There are no recommended or preferred methods for tapering off once-weekly injections like Mounjaro. With its half-life, Mounjaro will naturally leave your system over time.

“Any decision to stop should be made in consultation with your healthcare provider to ensure a smooth transition, whether it’s stopping cold turkey or considering a tapering approach if it aligns with clinical judgment,” Dr. Foxman says.

If you take a higher weekly dose (the maximum weekly dose is 15 mg) and are not experiencing any harmful symptoms, your healthcare provider may reduce your dose every four weeks to prevent out-of-control spikes. This taper schedule may be most helpful for those taking Mounjaro at maintenance over longer periods of time. However, tapering is not necessary for everyone.

RELATED: Mounjaro alternatives

How to keep weight off after Mounjaro

Continuing to follow any lifestyle changes, such as diet or exercise plans, is the best way to keep weight off after you stop using Mounjaro.

“I generally advise consuming a diet high in fiber, including fruits, vegetables, lean proteins, and whole grains; and limit intake of saturated fats, trans fats, sodium, and added sugars,” Dr. Mandal recommends. Moreover, keep portion sizes in mind. Because Mounjaro likely kept your appetite down, you’ll need to pay closer attention to this. Overeating can lead to weight gain and obesity, so closely manage your food intake. Dr. Mandal also recommends combining a healthy diet with moderate exercise three to four times per week.

If Mounjaro wasn’t the right medication for you—whether as a diabetes medication or weight loss drug—you may consider talking to your healthcare provider about other options. Ozempic and Wegovy (semaglutide) are the popular alternatives to Mounjaro and Zepbound. They are also glucagon-like peptide-1 (GLP-1) receptor agonists, but Ozempic is only approved for diabetes treatment, while Wegovy is for weight management.

Of course, keeping in touch with your healthcare provider after you’ve stopped using Mounjaro is important. Update them on any weight or blood sugar changes or if you experience any adverse side effects. They may have additional strategies and treatments for you to try.