Key takeaways

  • Common side effects of Trulicity (dulaglutide) include constipation, diarrhea, and fatigue. Most side effects of Trulicity are temporary and treatable. If you experience persistent or bothersome side effects during treatment, your doctor can recommend ways to manage them.
  • Dulaglutide works by telling your body to release more insulin, which helps lower your blood sugar. If you use too much Trulicity or use it with another insulin-stimulating drug (like Ozempic), your blood sugar could become dangerously low.
  • Certain medications, supplements, or foods may increase the risk of side effects with Trulicity or make the drug less effective. Before you start using Trulicity, talk with your doctor about what to avoid with Trulicity.

Keep reading to learn about the common, mild, and serious side effects that Trulicity can cause.

For a general overview of the drug, including details about its uses, see this article.

Boxed warning

Trulicity has a boxed warning. A boxed warning is the most serious warning from the Food and Drug Administration (FDA). For details, see the “Side effects explained” section.

Some people may experience mild or serious side effects during their Trulicity treatment. Examples of a few of Trulicity’s commonly reported side effects include:

In most cases, these side effects should be mild and temporary. And some may be easily managed, too. But if you have any symptoms that are ongoing or bothersome, talk with your doctor or pharmacist. And don’t stop using Trulicity unless your doctor tells you to.

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks and reviews side effects of the medication. Sharing your experience helps make medication safer for everyone by giving doctors and researchers more information about how the drug works in real life. If you develop a side effect while using Trulicity and want to tell the FDA about it, visit MedWatch or call 800-FDA-1088.

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In rare cases, Trulicity may cause serious side effects. Serious side effects that have been reported with Trulicity include:

If you develop serious side effects while taking Trulicity, call your doctor right away. If the side effects seem life threatening, or if you think you’re having a medical emergency, immediately call 911 or your local emergency number.

Allergic reaction

For some people, dulaglutide can cause an allergic reaction. Reactions that were reported in clinical studies include:

  • systemic (whole-body) hives
  • systemic rash
  • facial swelling

In general, allergic reactions can be mild or serious.

What might help

If you have mild symptoms of an allergic reaction, such as a mild rash, call your doctor right away. They may suggest a treatment to manage your symptoms and can determine whether you should keep using Trulicity.

If you have symptoms of a severe allergic reaction, such as swelling or trouble breathing, call 911 or your local emergency number right away. These symptoms could be life threatening and require immediate medical care.

If your doctor confirms you’ve had a serious allergic reaction to Trulicity, they may have you switch to a different treatment.

Neither Ozempic (semaglutide) nor Trulicity (dulaglutide) is objectively safer. The best treatment for you will depend on several factors, including your age, your specific condition, and how your body responds to a particular drug.

Because Trulicity and Ozempic work in similar ways, they share some side effects, and others differ. The table below compares and contrasts side effects reported in clinical trials of both Ozempic and Trulicity.

TrulicityOzempicBoth Ozempic and Trulicity
• atrioventricular block (AV block)

• bloating

• allergic reactions including hives, rash, and facial swelling 		• gastritis (inflammation of the stomach lining)

• dizziness

• changes in taste		• nausea

• vomiting

• diarrhea

• constipation

• low blood sugar

• rapid heartbeat

• injection site reactions



Below, find answers to some frequently asked questions about Trulicity’s side effects.

Lilly, the manufacturer of Trulicity, doesn’t have an online forum for side effect information. Although other online forums may exist to discuss Trulicity’s side effects (such as Reddit), the best way to learn about these possible effects is to talk with your doctor or pharmacist. Information in an online forum may not be reliable.

Trulicity does have a support program that you can sign up for. This program can provide you with resources, which may include information about side effects or tips for using Trulicity.

If you have any specific questions about side effects of Trulicity, talk with your doctor or pharmacist.

It depends. Side effects of Trulicity can vary, and they may last longer in some people than others.

For example, one possible side effect of Trulicity is an injection-site reaction. This may include rash, swelling, redness, or other discoloration in the area where you inject Trulicity. This side effect may occur right after an injection, or it may take time to develop.

Injection-site reactions usually go away a few days after you inject your dose. However, you may experience injection-site reactions with each dose of Trulicity.

Some people may experience nausea during their Trulicity treatment. This could occur a few days after starting the treatment or after your dose is increased. For most people, nausea usually goes away after about 2 weeks of treatment with Trulicity.

If you have concerns about specific side effects or how long they might last, talk with your doctor or pharmacist. They may be able to give you advice about how to prevent or treat these side effects.

Learn more about some of the side effects that ­­Trulicity may cause.

Boxed warning: Thyroid cancer

Trulicity has a boxed warning for the risk of thyroid cancer. A boxed warning is the most serious warning from the Food and Drug Administration (FDA). It alerts doctors and patients about drug effects that may be dangerous.

Animal studies have shown an increased risk of thyroid cancer from dulaglutide (the active ingredient in Trulicity). However, it’s not yet known if this risk also applies to humans.

Because of this possible risk, it’s important to watch for any symptoms of thyroid cancer. These symptoms may include:

  • a lump or swelling in your neck
  • trouble swallowing
  • trouble breathing

What might help

You and your doctor will talk about your health history before you start using Trulicity. You should not use Trulicity if:

  • you have a personal or family history of a specific type of thyroid cancer called medullary thyroid cancer
  • you have a condition called multiple endocrine neoplasia syndrome type 2

Due to the results of animal studies, it’s thought that using Trulicity if you have one of these risk factors could raise your risk for thyroid cancer. More research is needed to know whether Trulicity increases this risk in humans, though.

During your Trulicity treatment, tell your doctor right away if you notice any symptoms of thyroid cancer. They can screen you for thyroid cancer by checking for any lumps in your neck and doing blood tests throughout your treatment.

If you have concerns about your risk for developing thyroid cancer during your Trulicity treatment, talk with your doctor or pharmacist.

Injection-site reactions (such as a rash)

Some people may experience injection-site reactions while using Trulicity. However, this is not a commonly reported side effect of the drug. Injection-site reactions may include a rash, redness or other discoloration, or swelling in the area where you injected Trulicity.

What might help

To help avoid injection-site reactions, you should rotate injection sites with each Trulicity dose.

If you experience injection-site reactions while using Trulicity, talk with your doctor or pharmacist about how to treat this side effect. They may recommend a warm compress or ice to help reduce any swelling, redness, or other discoloration. In some cases, they may recommend a medication, such as ibuprofen (Advil, Motrin), to decrease the swelling.

Pancreatitis

Pancreatitis (swelling of the pancreas) is a rare but serious side effect that can occur while using Trulicity. Symptoms of pancreatitis may include:

  • severe abdominal pain
  • back pain
  • vomiting

What might help

Your doctor will ask you about your health history before recommending Trulicity. Tell them if you have a history of pancreatitis because this may put you at risk for developing the issue again. If you’ve had pancreatitis, your doctor may recommend a different treatment for your condition.

If you develop symptoms of pancreatitis during your Trulicity treatment, stop using Trulicity and see your doctor right away. If it’s confirmed that you have pancreatitis, your doctor will treat it and then recommend a different treatment that’s better suited for you. You should not restart Trulicity if you develop pancreatitis during your treatment.

Digestive problems

Trulicity may cause digestive problems in some people. This is a common side effect of the drug. Digestive problems can include symptoms such as:

You may have a higher risk for digestive problems if you use a higher dose of Trulicity. For example, in studies, more people using a 1.5-milligram (mg) dose of Trulicity reported digestive side effects than people using a 0.75-mg dose.

What might help

If you have digestive problems while using Trulicity, talk with your doctor or pharmacist. They may be able to recommend ways to reduce these side effects, such as taking other medications to ease the symptoms.

Before using Trulicity, discuss your health history with your doctor. Trulicity may not be right for you if you have certain medical conditions or other factors affecting your health. Be sure to talk with your doctor if any of the following apply to you:

  • history of pancreatitis
  • previous allergic reaction to Trulicity or any of its ingredients
  • upcoming surgery or medical procedure requiring anesthesia or sedation
  • history of chronic dehydration or acute kidney damage
  • history of gastroparesis or constipation
  • liver problems
  • diabetic retinopathy
  • history of gallbladder disease
  • pregnancy or breastfeeding

Q:

My doctor recommended that I use both metformin and Trulicity for my type 2 diabetes, but both drugs may cause digestive problems. How can I prevent these problems or treat them if they occur?

Anonymous

A:

It’s true that both metformin and Trulicity may cause digestive problems, such as nausea or diarrhea.

Your risk for digestive problems with metformin may be lower if you use the extended-release (ER) form. This is a tablet that slowly releases the drug over time. Taking metformin with food can also help limit or prevent digestive problems.

Also, both medications have a higher risk of causing digestive problems when higher dosages are used. Your doctor may start you on a low dosage, then slowly increase your dosage of either or both medications over time.

If you have digestive problems while using Trulicity and metformin together, talk with your doctor or pharmacist. They may be able to recommend ways to decrease these side effects, such as taking other medications to ease the symptoms. They may also have you stop using one of the medications and try a different drug for your condition.

The Healthline Pharmacist TeamAnswers represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.

Disclaimer: Healthline has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.