Victoza (liraglutide) is a prescription drug that’s used to manage high blood sugar in certain adults and children with type 2 diabetes. Victoza can interact with some supplements and with other drugs, such as insulins.

An interaction can occur because one substance causes another substance to have a different effect than expected. Interactions can also occur if you have certain health conditions.

Before you start using Victoza, tell your doctor and pharmacist about any prescription, over-the-counter, or other drugs you take. Sharing this information with them may help prevent possible interactions. (To learn whether Victoza interacts with herbs or vitamins and supplements, see the “Are there other interactions with Victoza?” section below.)

If you have questions about drug interactions that may affect you, talk with your doctor or pharmacist.

The table below lists drugs that may interact with Victoza. Keep in mind that this table does not include all drugs that may interact with Victoza. For more information about some of these interactions, see the “Drug interactions explained” section below.

Drug group or drug nameDrug examplesWhat can happen
insulins• insulin glargine (Lantus, others)
• insulin human (Novolin R, others)
can increase the risk of hypoglycemia (low blood sugar)
sulfonylureasglipizide (Glucotrol XL)
glimepiride (Amaryl)
can increase the risk of hypoglycemia
corticosteroidsprednisone
dexamethasone
can make Victoza less effective, especially if the corticosteroid is used long term
protease inhibitors• darunavir (Prezista)
• nelfinavir (Viracept)
can make Victoza less effective
chloroquinecan increase the risk of hypoglycemia

Certain health conditions or other factors could raise your risk of harm if you use Victoza. In such cases, your doctor may not prescribe Victoza for you. These are known as contraindications. The list below includes contraindications of Victoza.

If you have a personal or family history of medullary thyroid carcinoma (MTC): Victoza has a boxed warning about the risk of thyroid cancer. Your doctor will not prescribe Victoza if you have a personal or family history of MTC. To learn more, see the “Boxed warning” section at the beginning of this article.

If you have multiple endocrine neoplasia syndrome type 2 (MEN2): Victoza has a boxed warning about the risk of thyroid cancer. Your doctor will not prescribe Victoza if you have MEN2. To learn more, see the “Boxed warning” section at the beginning of this article.

If you’ve had an allergic reaction: If you’ve had an allergic reaction to Victoza or any of its ingredients, your doctor likely won’t prescribe Victoza for you. This is because using the drug could cause another allergic reaction. You can ask your doctor about other treatments that may be better options for you.

Before you start using Victoza, talk with your doctor if any of the factors above apply to you. Your doctor can determine whether Victoza is a safe option for you.

Victoza is not known to interact with alcohol. But Victoza and alcohol can cause some similar side effects, such as diarrhea and nausea. So you may be more likely to experience these side effects if you drink alcohol during your Victoza treatment.

If you have questions about Victoza and alcohol, talk with your doctor or pharmacist.

Learn more about certain drug interactions that can occur with Victoza.

Interaction with insulins

Victoza can interact with insulins, which are used to treat diabetes.

Examples of insulin medications include:

  • insulin glargine (Lantus, others)
  • insulin human (Novolin R, others)
  • insulin lispro (Humalog, others)

What could happen

Taking Victoza with an insulin drug can raise your risk of having hypoglycemia (low blood sugar). This occurs because both Victoza and insulin work by lowering your blood sugar.

What you can do

If you use Victoza with an insulin drug, your doctor may prescribe a lower dosage of Victoza or the insulin for you. You should not use a higher dose of either medication than your doctor prescribes.

If you use Victoza and an insulin together, talk with your doctor about what to do if you have mild symptoms of hypoglycemia. These may include trouble concentrating, hunger, and fatigue. Your doctor can suggest a plan to treat mild hypoglycemia, such as eating 15 grams (g) of fast-acting carbohydrates. Examples include 1/2 cup of juice, 1 tablespoon of honey, or 1 tablespoon of sugar.

Your doctor will also likely prescribe the medication glucagon for you if you’re using Victoza with an insulin. Glucagon treats symptoms of severe hypoglycemia, which is a medical emergency. It’s important to get emergency medical care even if you use glucagon to treat severe hypoglycemia.

If you have questions about taking Victoza with insulin, talk with your doctor or pharmacist.

Interaction with sulfonylureas

Victoza can interact with sulfonylureas, which are used to treat type 2 diabetes.

Examples of sulfonylurea drugs include:

What could happen

Victoza and sulfonylureas can both cause hypoglycemia. So taking these drugs together can raise your risk of experiencing this side effect.

What you can do

If you use Victoza with a sulfonylurea, your doctor may prescribe a lower dosage of Victoza or the sulfonylurea for you. You should not use a higher dose of either medication than your doctor prescribes.

If you’ll use Victoza with a sulfonylurea, talk with your doctor about how to treat mild hypoglycemia. Suggested treatments include consuming 15 grams (g) of fast-acting carbohydrates. Examples include 1/2 cup of juice, 1 tablespoon of honey, or 1 tablespoon of sugar.

Severe hypoglycemia is a medical emergency that requires immediate treatment. Your doctor will also likely prescribe the medication glucagon to you if you’re taking Victoza with a sulfonylurea. Glucagon is used to treat symptoms of severe hypoglycemia. After using glucagon, you should contact emergency services.

Interaction with corticosteroids

Victoza can interact with corticosteroids. These drugs are used to treat many conditions, including asthma and various skin conditions.

Examples of corticosteroid medications include:

What could happen

Corticosteroids can lower your blood sugar. If you’re taking a corticosteroid and Victoza together, this could cause your blood sugar to become too low.

What you can do

If you’re taking a corticosteroid short term with Victoza, your doctor may suggest closely monitoring your blood sugar level. But they may not need to adjust your Victoza dose. However, if you need to take a corticosteroid long term with Victoza, your doctor may adjust your Victoza dose.

Victoza may have other interactions. They could occur with supplements, foods, vaccines, or even lab tests. See below for details. Note that the information below does not include all other possible interactions with Victoza.

Does Victoza interact with supplements?

Before you start using Victoza, talk with your doctor and pharmacist about any herbs or vitamins and supplements you take. Sharing this information with them may help you avoid possible interactions.

If you have questions about interactions that may affect you, talk with your doctor or pharmacist.

Victoza interactions with herbs

Victoza can interact with garlic supplements, which may be used to manage blood sugar levels. Victoza is also used to lower blood sugar levels. So taking a garlic supplement while using Victoza may raise your risk of having low blood sugar.

For this reason, it’s important to check with your doctor or pharmacist before taking any of these products while using Victoza.

Victoza interactions with vitamins and minerals

Victoza can interact with chromium supplements, which may be used to manage blood sugar levels. Victoza is also used to lower blood sugar levels. Taking a chromium supplement while using Victoza may raise your risk of having low blood sugar.

For this reason, it’s important to check with your doctor or pharmacist before taking these products while using Victoza.

Does Victoza interact with food?

Victoza can interact with green tea. Green tea can lower your blood sugar, and Victoza is prescribed to lower blood sugar levels. So, consuming large quantities of green tea during your Victoza treatment can raise your risk of having low blood sugar.

If you have questions about other foods you may need to avoid while using Victoza, talk with your doctor or pharmacist.

Note: Although Victoza may interact with garlic supplements, it isn’t expected to interact with garlic used in food.

Does Victoza interact with vaccines?

There are currently no reports of Victoza interacting with vaccines. If you have questions about receiving certain vaccines during your Victoza treatment, talk with your doctor.

Does Victoza interact with lab tests?

There are currently no reports of Victoza interacting with lab tests. If you have questions about having certain lab tests done during your Victoza treatment, talk with the healthcare professional ordering the test.

Does Victoza interact with cannabis or CBD?

There are currently no reports of Victoza interacting with cannabis (commonly called marijuana) or cannabis products such as cannabidiol (CBD). But as with any drug or supplement, talk with your doctor before using cannabis with Victoza.

Note: Cannabis is illegal at a federal level but is legal in many states to varying degrees.

Certain medical conditions or other health factors may raise the risk of interactions with Victoza. Before using Victoza, talk with your doctor about your health history. They’ll determine whether Victoza is right for you.

Health conditions or other factors that might interact with Victoza include:

Pancreas problem, such as pancreatitis. Victoza may cause pancreatitis. If you have already have chronic (long-term) pancreatitis, taking Victoza could worsen your condition. You and your doctor can discuss the risks and benefits of using Victoza if you have chronic pancreatitis.

Gastroparesis or another digestive problem. It’s not known whether it’s safe to use Victoza if you have gastroparesis or another digestive problem. Victoza slows the speed at which your stomach digests food and empties its contents. So taking Victoza could worsen your digestive condition.

Pregnancy. It’s not known whether Victoza is safe to use during pregnancy. If you’re pregnant or planning a pregnancy, talk with your doctor before using Victoza.

Breastfeeding. It’s not known whether it’s safe to use Victoza while breastfeeding. If you’re breastfeeding or planning to breastfeed, talk with your doctor about your options.

Allergic reaction. If you’ve had an allergic reaction to Victoza or any of its ingredients, your doctor will likely not prescribe Victoza. This is because using the drug could cause another allergic reaction. You can ask your doctor about other treatments that may be better choices for you.

Find answers to some frequently asked questions about Victoza and possible interactions.

Can I use Victoza and atorvastatin together?

Yes, it’s safe to use Victoza and atorvastatin (Lipitor) together. These medications aren’t known to interact with each other.

Victoza is used to treat type 2 diabetes and lower certain risks related to your heart and blood vessels. Atorvastatin is used to lower cholesterol and to decrease certain risks related to the heart and blood vessels. Doctors may prescribe these drugs together in some cases.

If you have other questions about using Victoza and atorvastatin together, talk with your doctor or pharmacist.

Is it safe to use Victoza if I’m also taking a vitamin D supplement?

Yes, it should be safe to use Victoza with vitamin D supplements. There is no known interaction between Victoza and these supplements.

If you have other questions about using Victoza and vitamin supplements together, talk with your doctor or pharmacist.

Taking certain steps can help you avoid interactions with Victoza. Before starting treatment, talk with your doctor and pharmacist. Things to discuss with them include:

  • Whether you drink alcohol or use cannabis.
  • Other medications you take, as well as any vitamins, supplements, and herbs. Your doctor or pharmacist can help you fill out a medication list.
  • What to do if you start taking a new drug during your Victoza treatment.

It’s also important to understand Victoza’s label and other paperwork that may come with the drug. Colored stickers that describe interactions may be on the label. And the paperwork (sometimes called the patient package insert or medication guide) may have other details about interactions. (If you did not get paperwork with Victoza, ask your pharmacist to print a copy for you.)

If you have trouble reading or understanding this information, your doctor or pharmacist can help.

Using Victoza exactly as prescribed can also help prevent interactions.

If you still have questions about Victoza and its possible interactions, talk with your doctor.

Questions you may want to ask your doctor include:

  • Do I need to space out when I take my medications throughout the day to avoid interactions with Victoza?
  • Could I still use Victoza even if it interacts with a health condition I have?
  • Does my risk of interactions depend on my dosage of Victoza?

To learn more about Victoza, see these articles:

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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.