16 Tirzepatide Side Effects You Should Know About

Tirzepatide is a medication that’s sold under two brand names: Mounjaro and Zepbound. Mounjaro is FDA approved for Type 2 diabetes and to help reduce the risk of serious cardiovascular problems. Zepbound is approved for weight loss and obstructive sleep apnea. These medications have soared in popularity since coming to the U.S. market.

Not everyone who uses tirzepatide is receiving an FDA-approved version. Some people use compounded tirzepatide. This is when the medication is made by a compounding pharmacy. This version of tirzepatide can be helpful if you have a medical need for it, such as being allergic to an inactive ingredient in Mounjaro or Zepbound.

No matter which version of tirzepatide you use, they can all cause similar side effects. The most common tirzepatide side effects, such as nausea and diarrhea, affect the digestive system. But these aren’t the only ones to know about.

Tirzepatide side effects at a glance

Most tirzepatide side effects are mild and can be managed at home with lifestyle changes. But in rare cases, more serious risks have been reported by people using the medication. Because they both contain tirzepatide, Mounjaro side effects and Zepbound side effects are similar.

Common tirzepatide side effects include:

• Nausea

• Vomiting

• Diarrhea

• Constipation

• Smaller appetite

• Weight loss (often an intended effect)

• Heartburn or acid reflux

• Indigestion

• Stomach discomfort or bloating

• Burping, including “sulfur burps”

• Flatulence (gas)

• Fatigue

• Dizziness

• Headaches

• Mildly low blood pressure, especially if you take blood pressure medications

• Small heart rate increases

• Temporary hair loss

• Injection site reactions

• Body aches

• Vivid dreams

• Facial changes

• Rebound weight gain if you stop using tirzepatide

• Taste changes

• Dysesthesia (an unusual sensation on your skin)

Rare but serious tirzepatide side effects and risks include:

• Pancreatitis (swelling of the pancreas)

• Gallbladder disease, including gallstones

• Kidney damage following severe vomiting or diarrhea

• Low blood glucose (blood sugar)

• Severe gastrointestinal reactions, such as bowel obstructions (blockages)

• Temporary worsening of diabetic retinopathy (eye problems caused by diabetes)

• Non-arteritic anterior ischemic optic neuropathy (a rare eye condition that can cause permanent vision loss in severe cases)

• Allergic reactions

Mounjaro and Zepbound also have boxed warnings for thyroid C-cell tumors. A boxed warning is the FDA’s strictest warning for medications. Because of this risk, you shouldn’t use tirzepatide if you have a family or personal history of certain thyroid cancers (more detail later).

Below are 16 tirzepatide side effects to know about, plus ways you can manage them.

1. Nausea and vomiting

Tirzepatide commonly causes nausea and vomiting. This is especially true when you first start using it. You may also notice it more shortly after raising your dosage. Nausea and vomiting should improve over time. These side effects happen because of how tirzepatide works.

Tirzepatide helps food stay in your stomach longer. This is called slowed gastric emptying. It helps you feel fuller after eating and helps your body balance blood sugar levels. But slowed gastric emptying can cause nausea, vomiting, and other digestive side effects.

If you feel nauseated while using tirzepatide, here are some tips to help manage it:

• Stick to your prescribed dosage schedule. Don’t raise your dose faster than what’s recommended.

• Eat several small meals per day, instead of 2 or 3 large meals.

• Stop eating when you feel full.

• Avoid fatty foods and alcohol.

• Remain upright for about 30 minutes after eating.

• If you’re vomiting, make sure you stay well hydrated. Try ginger tea, it’s good for hydration and can help with nausea.

• Eat bland foods, such as bananas or toast, for a few days when nausea or vomiting is at its worst.

If vomiting is severe or persistent, tell your healthcare team. This can lead to dehydration over time. And in serious cases, dehydration can cause kidney damage (more on this later).

2. Diarrhea

Diarrhea is another common tirzepatide side effect. It tends to be worse when you first start the medication. It should improve as your body adjusts to it.

In the meantime, here are some tips for managing diarrhea:

• Make sure you’re getting plenty of hydrating fluids.

• Avoid alcohol.

• Limit or avoid greasy and spicy foods.

• Limit caffeine until your body adjusts to tirzepatide.

• Limit or avoid dairy products, such as milk.

Ask a healthcare professional before trying over-the-counter (OTC) antidiarrheal medications. These can be helpful for some people with diarrhea. But it’s usually best for most people to manage this tirzepatide side effect with dietary changes.

If diarrhea is severe or not improving with time, tell your healthcare team. This can lead to dehydration and kidney damage.

3. Constipation

Constipation is a tirzepatide side effect caused by slowed gastric emptying. Like other common side effects, it’s typically worse when first starting the medication. After you’ve been on the same dose for a while, it usually improves or resolves.

There are things you can try that may relieve constipation from tirzepatide:

• Increase the amount of fluids you’re drinking.

• Slowly incorporate more fiber in your diet. But be aware that adding fiber too fast may make constipation worse.

• Add more exercise or movement to your routine in a way that’s fun for you.

• Ask a healthcare professional about OTC constipation medications. Short-term use of these medications can be helpful for some people.

If your constipation is severe or not getting better, tell your healthcare team.

4. Stomach discomfort and bloating

Stomach discomfort and bloating are also common with tirzepatide. Slowed gastric emptying causes these side effects. They can be uncomfortable or even painful. But they tend to improve as your body adjusts to the medication.

Consider these tips to help relieve stomach discomfort:

• Try to limit caffeine, dairy products, and carbonated beverages (especially when first starting tirzepatide).

• If constipation is the cause of your stomach pain, slowly add more fiber to your diet.

• Ask a healthcare professional about taking simethicone (Gas-X) for bloating.

If you’re having severe stomach pain or you have jaundice (yellowing of the skin or eyes), seek medical help. These can be symptoms of more severe issues, such as pancreatitis or gallbladder problems.

5. Indigestion

Tirzepatide can also cause indigestion. This can include upset stomach, heartburn, or acid reflux. Tirzepatide’s effects on stomach emptying can cause these symptoms. But as your body adjusts to the medication, indigestion should improve over time.

There are several things you can do at home to help manage indigestion, such as:

• Eat five or six smaller meals per day, rather than a few large meals.

• Avoid lying down right after eating.

• Avoid drinking alcohol. This can trigger or worsen acid reflux.

• Limit caffeine, soda, and acidic or spicy foods.

• Try not to eat right before bed.

• Elevate your head while sleeping with a wedge or extra pillows.

• Ask your healthcare team about taking OTC acid reflux medications.

6. Gas and sulfur-smelling burps

Tirzepatide also commonly causes gas and burping. Like most other digestive side effects, these happen with tirzepatide because food is leaving your stomach more slowly.

Some people using tirzepatide report having sulfur-smelling burps (burps that smell like rotten eggs). If this happens to you, try reducing the amount of high-sulfur foods you eat, such as:

• Dried fruits

• Nuts

• Wine and beer

• Cruciferous vegetables, such as broccoli, cabbage, and kale

Gas and burping should improve as your body gets used to tirzepatide. Many of the tips that help with indigestion can also relieve gas and burping. OTC products, such as simethicone and bismuth subsalicylate (Pepto-Bismol, Kaopectate), may also help.

7. Decreased appetite and weight loss

Tirzepatide typically causes a decreased appetite and weight loss. For many people using the medication, these are the intended effects. But if you’re not using tirzepatide for weight loss, it could be surprising.

A decreased appetite can make it harder to want to eat. And in turn this makes it challenging to consume the nutrients you need. Here are some tips that can help you eat and get nutrients when you’re not feeling hungry:

• Pick high-protein foods and snacks, such as greek yogurt.

• Opt for smoothies. Try adding your favorite fruits and veggies or mix in a protein source, such as avocado.

• Try easy-to-digest foods, such as toast with your favorite nut butter.

• Make your meals nutrient-dense. Fruits and eggs are two examples that are packed with nutrients and easier to eat when you’re not hungry.

If you find that you’re not hungry at all or you feel lost when it comes to meal planning, tell your healthcare team. You may also want to consider meeting with a dietitian. They can work with you to develop a dietary plan that works alongside your health goals.

8. Fatigue, tiredness, and dizziness

Fatigue, tiredness, and dizziness are not as common as other tirzepatide side effects. But they’re still possible.

A possible reason for these tirzepatide side effects is that a smaller appetite makes it hard to eat the right nutrients. Another possible cause of fatigue is that tirzepatide’s digestive side effects might interfere with sleep.

Regardless of why you’re feeling tired or dizzy, there are things you can do about it:

• Take steps to make sure you’re getting enough rest at night. For adults, that’s about 7 to 9 hours each night.

• Stay hydrated. Fatigue and dizziness can be early symptoms of dehydration.

• Take your time changing positions. Standing or sitting too quickly can make dizziness worse.

• Eat foods and snacks that have essential nutrients. Focus on lean proteins, fiber, and healthy fats.

• Try to stay active. Even gentle exercises, such as walking, can help energize you.

If dizziness seems severe or causes you to fall, tell your healthcare team. This isn’t an expected tirzepatide side effect.

9. Headaches

Some people report headaches while using tirzepatide. Evidence suggests that the medication doesn’t directly cause them. It’s more likely that other tirzepatide side effects are contributing to headaches.

For example, diarrhea is common while using tirzepatide. If you have loose stools and you’re not drinking enough fluids, you may become dehydrated. And headaches are one symptom of dehydration.

Typically, managing other tirzepatide side effects should help resolve headaches. But if needed, OTC pain relievers, such as acetaminophen (Tylenol), can relieve this symptom. Just be sure to ask a healthcare professional first if it’s safe for you to take OTC pain relievers.

10. Changes in blood pressure and heart rate

Tirzepatide may cause mild drops in blood pressure for some people. This may be especially true if you also take blood pressure medications. Tirzepatide may also cause a slightly elevated heart rate.

These heart-related side effects aren’t generally harmful. And people living with hypertension (high blood pressure) can safely take tirzepatide. In fact, one tirzepatide product (Mounjaro) is approved to help reduce the risk of serious cardiovascular problems among certain adults.

Still, it’s good to tell your healthcare team if you have any heart-related health conditions. They should consider this when deciding if tirzepatide is right for you. They can also let you know if you should monitor your blood pressure or heart rate at home while using the medication.

11. Temporary hair loss

Some people experience temporary hair loss while using tirzepatide. In most cases, this looks like an increase in hair shedding.

Hair loss is an indirect side effect of tirzepatide. Significant weight loss — regardless of whether it’s supported by a medication — can lead to temporary hair loss. This is called telogen effluvium. It usually happens a few months after you start losing weight. Once your body adjusts to changes in body weight, hair shedding should return to normal.

If you notice chunks of hair falling out or see bald patches, tell your healthcare team. This is not the type of hair loss that happens with tirzepatide.

12. Injection site reactions

Tirzepatide comes as an injection. And all injectable medications can cause injection site reactions. You may notice pain, redness, or itching where you injected your dose.

Injection site reactions are expected and are not a sign of an allergic reaction. They should be mild and limited to the area of skin where you injected your dose. A reaction should resolve on its own within a few days of administering tirzepatide.

Applying a cool compress can help relieve injection site discomfort. You can also ask your healthcare team if it’s OK for you to take OTC pain relievers.

Be sure to always wipe your injection site with alcohol and let it dry before injecting tirzepatide. And be sure to rotate your injection site with each dose. These steps can help prevent injection site reactions.

13. Pancreatitis

In rare cases, people using tirzepatide developed pancreatitis. Researchers, though, haven’t found that the medication directly causes this condition. Pancreatitis is a medical emergency. It requires care in a hospital and can be fatal if left untreated.

Seek immediate medical help if you have symptoms of pancreatitis, such as:

• Severe upper right stomach pain

• Nausea and vomiting

• Jaundice

• Fever

• Low blood pressure

If you have a history of pancreatitis, tell your prescriber before starting tirzepatide. They may suggest avoiding the medication.

14. Gallbladder disease

Tirzepatide can also cause gallbladder disease, including gallstones and cholecystitis (gallbladder inflammation). This is very rare. But it’s painful and may require treatment in a hospital.

Keep in mind that people receiving a placebo (an injection without medication) in Mounjaro’s and Zepbound’s clinical trials also experienced gallstones. This is because weight loss in general can raise your risk of the condition.

Symptoms of gallbladder problems are similar to those of pancreatitis:

• Severe upper right stomach pain

• Nausea

• Vomiting

• Jaundice

• Fever

If you experience the symptoms above, seek medical help right away.

15. Kidney damage

In most cases, tirzepatide doesn’t cause kidney damage. In fact, it may help protect the kidneys for certain people. But if you experience severe or persistent vomiting or diarrhea, you may experience dehydration. And dehydration can cause acute (sudden) kidney damage.

Staying well hydrated can help prevent dehydration and kidney damage. And be sure to tell your healthcare team if vomiting or diarrhea seem severe or don’t improve over time.

Your healthcare team may ask you to go for blood work called a kidney function test while using tirzepatide. This test helps healthcare professionals spot early signs of dehydration and kidney damage. It’s best to go for any recommended blood tests on time.

16. Thyroid tumors

Mounjaro and Zepbound have boxed warnings for C-cell tumors. These types of tumors were seen in animal studies of tirzepatide. Researchers haven’t confirmed this risk in humans.

To be safe, it’s recommended to avoid tirzepatide if you have:

• A personal or family history of medullary thyroid cancer

• A personal history of an inherited condition called multiple endocrine neoplasia (MEN) type 2

When should you contact a healthcare professional about tirzepatide side effects?

If you experience any severe or persistent tirzepatide side effects, tell a healthcare professional. Managing more common issues, such as diarrhea, can often lower your risk of serious complications, such as kidney damage.

While rare, allergic reactions are possible with tirzepatide. Call 911 or go to the ER if you have symptoms of a serious allergic reaction, such as:

• Widespread rash

• Swelling of the face, tongue, or throat

• Tightness of the throat

• Trouble breathing

Frequently asked questions

Why trust our experts?

Written by:

Christina Aungst, PharmD, MWC

Christina Aungst, PharmD, MWC is a senior pharmacy editor for GoodRx. She began writing for GoodRx Health in 2019.

Reviewed by:

Stacia Woodcock, PharmD

Stacia Woodcock, PharmD, is a pharmacy editor for GoodRx. She earned her Doctor of Pharmacy degree from the University of Kentucky and is licensed in New York and Massachusetts.

Our editorial standards

Meet our experts