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Mounjaro® Important Safety Information | WW USA

Important Mounjaro® Safety Information

Most Important Safety Information

  • In rats, tirzepatide caused thyroid C-cell tumors, including medullary thyroid cancer. It is not known if Mounjaro will cause thyroid C-cell tumors or medullary thyroid carcinoma (MTC) in people. Tell your provider if you get a lump or swelling in your neck, hoarseness, trouble swallowing, or shortness of breath. These may be symptoms of thyroid cancer.
  • Do not use Mounjaro if you or any of your family have ever had a type of thyroid cancer called medullary thyroid carcinoma (MTC) or if you have an endocrine system condition called Multiple Endocrine Neoplasia syndrome type 2 (MEN 2).
  • Do not use Mounjaro if you have had a serious allergic reaction to tirzepatide or any of the ingredients in Mounjaro.

What is the FDA-approved use of Mounjaro?

Mounjaro is a glucose-dependent insulinotropic polypeptide (GIP) receptor and glucagon-like peptide-1 (GLP-1) receptor agonist that is used with diet and exercise to improve glycemic control in patients with type 2 diabetes mellitus.

Limitations of Use:

  • Mounjaro has not been studied in patients with a history of pancreatitis.
  • Mounjaro is not for treatment of type 1 diabetes mellitus.

What should I tell my provider before using Mounjaro?

Drugs you are taking. It’s important to tell your provider all of the medications you are currently taking, including prescription, over-the-counter medications, vitamins, and herbal and dietary supplements. Tell your provider if you are taking medicines to treat diabetes including insulin which could increase your risk of low blood sugar.

Your entire medical history. In particular, tell your provider if you have a past history of:

  • Type 1 or type 2 diabetes
  • Medullary thyroid carcinoma (MTC) or Multiple Endocrine Neoplasia syndrome type 2 (MEN 2)
  • Pancreatitis
  • Gallbladder Issues
  • Severe problems with your stomach, including gastroparesis or problems digesting food
  • Kidney disease
  • Diabetic retinopathy
  • History of Eating Disorders
  • Depression
  • Suicidal thoughts or behavior, or other mental health issues
  • History of a suicide attempt

Whether you are pregnant, planning to become pregnant, or breastfeeding.

  • If you are pregnant: Mounjaro should not be used during pregnancy. Based on animal studies, there may be potential risks to an unborn baby from exposure to Mounjaro during pregnancy.
  • If you are planning to become pregnant: Mounjaro may reduce the efficacy of oral hormonal contraceptives. Switch to a non-oral contraceptive method, or add a barrier method of contraception for 4 weeks after starting medication and for 4 weeks after each dose escalation until you reach a maintenance dose.
  • If you are breastfeeding: It is not known if Mounjaro passes into breast milk. Talk to your provider first about the benefits and risks of using Mounjaro while breastfeeding.

Pregnancy registry: There will be a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to Mounjaro during pregnancy. Pregnant patients exposed to Mounjaro and healthcare providers are encouraged to contact Eli Lilly and Company at 1-800-LillyRx (1-800-545-5979).

Withholding or providing inaccurate information about your health and medical history in order to obtain treatment may result in harm, including, in some cases, death.

What drug interactions do I need to be aware of?

Some medications to watch out for include:

  • Insulin
  • Sulfonylureas (these can cause blood sugar levels to drop dangerously low when combined with Mounjaro)
  • Hormonal birth control pills (Mounjaro may decrease its efficacy, especially after the first dose)
  • Other GLP-1 receptor agonist medications such as liraglutide, dulaglutide, or semaglutide.
  • You should limit your alcohol intake while taking this drug because alcohol can lower blood sugar. Combining alcohol with Mounjaro may cause blood sugars to fall too fast, leading to fainting and dizziness.
  • Other products for weight loss, including dietary supplements

What are the most serious side effects that I or a caregiver should monitor for when taking Mounjaro?

If you are experiencing a medical emergency, call 911 or seek immediate medical attention.

These serious side effects can occur with Mounjaro. You or a caregiver should carefully monitor for these side effects, especially in the beginning of treatment and with dose changes.

  • Thyroid C-Cell Tumors: In rats, tirzepatide caused a dose-dependent and treatment-duration-dependent increase in thyroid C-cell tumors. It is unknown whether Mounjaro causes thyroid C-cell tumors in humans. Mounjaro is contraindicated in patients with a family history of medullary thyroid cancer (MTC) or in patients with Multiple Endocrine Neoplasia syndrome type 2 (MEN 2). Tell your provider if you get a lump or swelling in your neck, hoarseness, trouble swallowing, or shortness of breath. These may be symptoms of thyroid cancer.
  • Severe Gastrointestinal Disease: Mounjaro is associated with gastrointestinal side effects, such as nausea, diarrhea, vomiting, constipation, and stomach pain, and can sometimes be severe. It hasn’t been studied in patients with severe gastrointestinal disease and isn’t recommended in these patients.
  • Acute Kidney Injury: Use of Mounjaro has been associated with gastrointestinal side effects, sometimes severe, which can lead to dehydration. If severe, dehydration could cause acute kidney injury. It is important for you to drink plenty of water to help reduce your chance of dehydration.
  • Acute Gallbladder Disease: Mounjaro and other GLP-1 receptor agonists are associated with an increased chance of acute gallbladder disease. Tell your provider right away if you have pain in your upper stomach, yellowing of skin or eyes (jaundice), fever, or clay-colored stools.
  • Inflammation of Pancreas (Acute Pancreatitis): Monitor for signs of acute pancreatitis, including severe abdominal pain that does not go away, sometimes radiating to the back, with or without vomiting.
  • Allergic Reactions: Stop using Mounjaro right away if you experience symptoms of a serious allergic reaction, including swelling of your face, lips, tongue or throat, severe rash or itching, very rapid heartbeat, problems breathing or swallowing, or fainting or feeling dizzy.
  • Low Blood Sugar (Hypoglycemia): Mounjaro lowers blood glucose. It can cause too low blood sugar in patients with type 2 diabetes who also take another glucose control medication. Monitor your blood sugar and watch out for signs of too low blood sugar such as dizziness, blurred vision, mood changes, sweating, or fast heartbeat.
  • Diabetic Retinopathy Complications in Patients with a History of Diabetic Retinopathy: Rapid improvement of glucose control has been associated with temporary worsening of diabetic retinopathy. Tell your provider right away if you experience changes in vision.
  • Suicidal Behavior and Ideation: You should pay attention to any mental health changes, especially sudden changes in your mood, behaviors, thoughts, or feelings. Call your healthcare provider right away if you have any mental changes that are new, worse, or worry you.
  • Never Share a Pen: Pen-sharing poses a risk of infection.

These common side effects can occur with Mounjaro.

  • Nausea
  • Diarrhea
  • Vomiting
  • Constipation
  • Stomach pain
  • Indigestion
  • Decreased appetite

You are encouraged to report negative side effects of prescription products:

This information is not comprehensive. Please see the full Prescribing Information for complete safety information.

Disclaimer: Mounjaro® is a registered trademark of Eli Lilly.