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Mounjaro® Side Effects
Connect with an attorneyMounjaro® is a prescription medication approved to treat Type 2 diabetes and has an off-label use as a weight loss drug to treat obesity. Common reported side effects of Mounjaro include abdominal pain, constipation and nausea. However, some patients are experiencing unexpected side effects, including gastroparesis and gastroenteritis.
How Mounjaro Works
Mounjaro works by mimicking two of the body's digestive hormones: glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1). These work together to regulate blood sugar levels and reduce appetite by activating satiety signals in the body.
Patients taking Mounjaro may experience weight loss as a side effect of the medication, but it is not an on-label use for people without type 2 diabetes.
Unexpected Mounjaro side effects
Mounjaro manufacturer Eli Lilly failed to include some of the most serious alleged side effects and adverse reactions on the warning label, including gastroparesis and gastroenteritis. Some patients are filing Mounjaro lawsuits after experiencing severe illnesses not mentioned on the label. Plaintiffs believe Eli Lilly was aware of the potential for severe gastrointestinal side effects and other complications from clinical studies, but they chose not to warn that people could suffer these effects as a result of taking Mounjaro.
Gastroparesis
Gastroparesis is a medical condition that impacts your stomach's ability to move food through your digestive system. The GLP-1 receptor agonists in Mounjaro reduce gastric emptying, which can be an issue for some patients and lead to gastroparesis.
With gastroparesis, the movement of your stomach muscles is inhibited, which is why it’s often called “paralyzed stomach.” Gastroparesis can lead to severe complications, including blocked intestines (ileus) if it isn’t treated. To make matters worse, gastroparesis has no cure.
Common symptoms associated with gastroparesis include:
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Patients across the country are taking legal action with diabetes lawsuits involving drugs like Mounjaro after gastroparesis dramatically affected their lives. In one lawsuit against Eli Lilly, a female plaintiff was diagnosed with gastroparesis after using Mounjaro. The lawsuit claims the drug prevented the victim from properly digesting food, prompting doctors to insert a feeding tube to ensure she received adequate nutrition. She was also hospitalized multiple times due to complications with the feeding tube. This lawsuit is looking to hold Eli Lilly accountable because they didn’t disclose the risk of gastroparesis on Mounjaro’s boxed warning label.
Consult your doctor if you experience symptoms of gastroparesis or any other serious side effects while taking Mounjaro.
Gastroenteritis
Gastroenteritis refers to inflammation and irritation of the stomach and intestines. Gastroenteritis is the medical term for the stomach flu, which occurs when the immune system responds to an infection. Certain medications, including Mounjaro, can also trigger gastroenteritis.
Patients taking Mounjaro may experience gastroenteritis. However, despite patient complaints of gastrointestinal distress, Mounjaro does not disclose the risk of gastroenteritis on-label or in the “Important Safety Information” section of its website.
Symptoms of gastroenteritis might include:
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Patients with gastroenteritis are at an increased risk of dehydration caused by vomiting and diarrhea, which can lead to death. Symptoms of gastroenteritis dehydration include dizziness, dry mouth, dry skin or increased thirst.
If you are taking Mounjaro and develop symptoms of dehydration or experience new or worsening side effects, do not hesitate to contact your doctor. They may be able to help treat your symptoms and report your adverse reactions to the U.S. Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS). FAERS is an important database that allows the FDA to monitor reactions and severe side effects associated with prescription medications.
Contact a Mounjaro attorney
Complete this webform or call 1.800.768.4026 to contact an attorney for more information or to discuss a potential Mounjaro long-term side effects claim.
On-label Mounjaro side effects
Potential side effects of Mounjaro and adverse reactions could include abdominal pain, constipation, decreased appetite, diarrhea, upset stomach (dyspepsia) or nausea. There are also several serious Mounjaro risks patients should be aware of, including:
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About 5% or more of patients using Mounjaro reported having the most common side effects and adverse reactions. If you begin to experience any of the side effects associated with Mounjaro use, you should report them to your doctor.
Acute gallbladder disease
Acute gallbladder disease, also known as acute cholecystitis, refers to chronic gallbladder inflammation. Gallbladder problems typically require hospitalization for treatment. It can cause symptoms, including:
- Abdominal tenderness
- Extreme pain in your center or upper right abdomen
- Fever
- Nausea
- Pain that radiates to your back or right shoulder
- Vomiting
If you begin to experience sharp or sudden pains in your belly that begin to radiate to your back or shoulders, contact your healthcare provider to prevent worsening symptoms.
Diabetic retinopathy
Diabetic retinopathy is a complication often seen in patients with Type 1 or Type 2 diabetes. Since patients may already be at a higher risk for diabetic retinopathy, the risk increases with the use of a tirzepatide medication. The condition occurs when the blood vessels at the back of the eye (the retina) are damaged. Potential symptoms associated with diabetic retinopathy include:
- Blurred vision
- Dark areas in your vision
- Empty areas in your vision
- Floaters or dark strings that seem to float in your line of sight
- Fluctuating vision
- Spots in your vision
- Vision loss
Initially, patients with diabetic retinopathy may experience no or mild symptoms. However, over time and without treatment, diabetic retinopathy can advance and lead to blindness.
Dyspepsia
Dyspepsia is a medical condition also known as a chronic upset stomach. Similar to the symptoms you might see with an ulcer, potential signs of dyspepsia include:
- Bloating
- Burning in the stomach
- Discomfort in the upper abdominal region
- Excessive belching
- Feeling full after eating only a couple of bites of food
- Nausea and vomiting
- Pain in the stomach
Hypersensitivity reactions
Some patients may experience a hypersensitivity reaction after taking Mounjaro. Essentially when this occurs, the body reacts to the medication by perceiving it as a threat to the body and mounting an immune system response to the drug.
Multiple hypersensitivity reactions could occur depending on how the body responds to Mounjaro. These include:
- Type 1: Symptoms usually appear immediately after you are exposed to a trigger. Type 1 hypersensitivity reactions might include cardiac symptoms, edema, flushing, hives, itching, loss of consciousness, nausea, rash, rhinitis, shortness of breath, stomach cramps, vomiting or wheezing. Type 1 hypersensitivity reactions produce the IgE antigen.
- Type 2: In this reaction, healthy cells die when they respond to the perceived threat. These cytotoxic reactions can cause cell and tissue damage, such as blood disorders and autoimmune conditions. When this occurs, Type 2 hypersensitivity reactions produce both the IgE and IgN antibodies.
- Type 3: With Type 3 hypersensitivity reactions, the antibodies and antigens form complexes that cause additional reactions and lead to tissue damage in the kidneys, blood vessels, joints and skin. Type 3 hypersensitivity reactions can also lead to small vessel vasculitis, serum sickness, rheumatoid arthritis, lupus and Henoch-Schönlein purpura (bleeding in the small blood vessels).
- Type 4: White blood cells, known as T-cells, are responsible for Type 4 hypersensitivity reactions. These reactions are unique compared to the other types, as Type 4 causes delayed reactions.
- Type 5: When antibodies target receptors on cells, Type 5 hypersensitivity reactions can occur. This reaction occurs because hormones normally activate the receptors on these cells.
Talk with your physician about how to manage the side effects of hypersensitivity reactions while taking Mounjaro. In some cases, your healthcare provider may recommend stopping the tirzepatide medicine if your body is not responding to it well.
Hypoglycemia with the use of insulin
When combined with insulin, Mounjaro has the potential to cause hypoglycemia or low blood sugar. Some potential signs and symptoms of hypoglycemia might include:
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Kidney failure
Kidney failure, often called renal failure, happens when one or both kidneys cannot function independently. Common symptoms of kidney failure include:
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Acute kidney failure will require immediate medical attention. If you are experiencing any of these symptoms while taking Mounjaro, contact your doctor right away.
Pancreatitis
Pancreatitis, or inflammation and swelling of the pancreas, occurs when the enzymes and digestive juices begin to attack the pancreas. Potential symptoms associated with pancreatitis could include:
- Abdominal pain
- A buildup of abdominal fluid
- Fever
- Jaundice (yellowing of the eyes or skin)
- Lowered blood pressure
- Nausea
- Rapid heart rate
- Soreness or swelling in the upper belly
- Vomiting
Every person's symptoms of this Mounjaro side effect may vary. While experiencing one of these symptoms may not be a cause for concern, multiple side effects could indicate pancreatitis or other adverse reactions.
Severe gastrointestinal disease
Gastrointestinal diseases can be functional or structural and affect your entire gastrointestinal tract. Functional gastrointestinal diseases may cause the bowel to look normal initially but fail to function properly. Structural gastrointestinal diseases cause the bowel to appear and function abnormally. In some cases, abnormalities may require surgical intervention. Mounjaro’s warning label does not specifically include gastroparesis or gastroenteritis.
Some examples of gastrointestinal diseases could include:
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Thyroid C-cell tumors
One of the most severe adverse reactions associated with Mounjaro is the development of medullary thyroid cancer (MTC). Patients may initially find nodules or lumps in the thyroid when they examine their necks. MTC can metastasize to the lymph nodes. Some common symptoms of thyroid cancer include:
- Difficulty breathing
- Ear pain
- Hoarseness
- Jaw pain
- Neck pain
- Trouble swallowing
While MTC may be considered a more aggressive type of cancer, according to the American Thyroid Association, if diagnosed before it spreads, it may be easier to treat.
Frequently Asked Questions About Mounjaro Side Effects
What are some of the most common side effect of Mounjaro?
Some of the most common side effects of Mounjaro are gastrointestinal and digestive issues. Side effects also include abdominal pain, constipation, diarrhea, nausea and vomiting. Other common side effects could include cramping, dizziness, back pain, loss of appetite and weight loss.
What are the side effects of using Mounjaro for weight loss?
Mounjaro is not an FDA-approved weight loss drug, so the side effects of this use are still being researched. However, some patients using Mounjaro to treat obesity have reported multiple side effects after starting Mounjaro, including abdominal pain, allergic reaction, constipation, decreased appetite, diarrhea, heartburn, indigestion, injection site sensitivity, nausea and vomiting. These could indicate something more serious, and you should report any side effects you have to your doctor.
Does Mounjaro cause headaches?
Mounjaro may cause headaches in patients who eat at a reduced caloric intake because of decreased appetite. However, headaches are not considered a common side effect of Mounjaro.
How long do Mounjaro side effects last?
Mounjaro side effects can last for a couple of days or several weeks. More mild side effects, such as nausea or diarrhea, may decrease once your body gets used to Mounjaro. However, the more serious side effects and adverse reactions, like gastroenteritis and gastroparesis, may last longer.
What are the long-term side effects of Mounjaro?
Patients taking Mounjaro may have an increased risk of experiencing long-term side effects, including gastroenteritis and gastroparesis. Gastroparesis can paralyze stomach mobility, making pushing food through the digestive system difficult or impossible. A paralyzed stomach can lead to acid reflux, malnutrition and vomiting. Patients may continue to experience gastroparesis even after stopping Mounjaro, as there is no cure. Gastroenteritis is inflammation in the stomach that causes extreme vomiting, which can lead to dehydration and possibly death.
Our medical drug litigation experience
Our attorneys have spent decades advocating for patients who suffer serious medical conditions as a result of taking dangerous over-the-counter diabetes medications and prescription diabetes and weight loss drugs.
If you suspect your use of Mounjaro, another tirzepatide or semaglutide medication has caused long-term side effects that have had a devastating impact on your life, contact our legal team. We understand that people who are negatively impacted want to hold drug manufacturer Eli Lilly accountable for failing to warn patients of all the Mounjaro risks. We can use our resources to conduct an intensive investigation and:
- Investigate whether Mounjaro is responsible for your symptoms
- Gather evidence to help prove Eli Lilly failed to comply with FDA drug label regulations
- Review the Mounjaro warning label to identify potential off-label side effects
- Identify problems that could impact your potential claim
Read more on our medical drug litigation experience.
Do not stop taking a prescribed medication without first consulting with your doctor. Discontinuing a prescribed medication without your doctor's advice can result in injury or death. Mounjaro remains approved by the U.S. Food and Drug Administration.
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