Ingrezza (valbenazine) is a prescription oral capsule that’s used to treat tardive dyskinesia and chorea resulting from Huntington’s disease in adults. It can interact with other medications and some supplements. For example, Ingrezza can interact with the drugs paroxetine and ketoconazole.
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.
Keep reading to learn about Ingrezza’s possible interactions. And for more information about Ingrezza, including details about its uses, see this article.
Certain health conditions or other factors could raise your risk of harm if you take Ingrezza. In such cases, your doctor may not prescribe Ingrezza for you. These are known as contraindications. Ingrezza has one contraindication, which is described below.
If you’ve had an allergic reaction. If you’ve had an allergic reaction to Ingrezza or any of its ingredients, your doctor likely won’t prescribe Ingrezza. 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.
There’s no known interaction between Ingrezza and alcohol. But Ingrezza and alcohol can cause similar side effects, such as nausea and tiredness. Both Ingrezza and alcohol can also cause long QT syndrome, which can be serious.
Combining Ingrezza and alcohol can raise your risk of these side effects or could make them more severe.
If you drink alcohol, talk with your doctor about how much (if any) may be safe to consume during your Ingrezza treatment.
Before you start taking Ingrezza, 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 Ingrezza interacts with supplements, herbs, and vitamins, see the “Are there other interactions with Ingrezza?” 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 Ingrezza. Keep in mind that this table does not include all drugs that may interact with Ingrezza. For more information about some of these interactions, see the “Drug interactions explained” section below.
| Drug group or drug name | Drug examples | What can happen |
| Monoamine oxidase inhibitors (MAOIs) | • isocarboxazid (Marplan) • phenelzine (Nardil) | can increase the risk of side effects of MAOIs or can make Ingrezza less effective |
| Drugs that slow the activity of the CYP3A4 enzyme | • ketoconazole • itraconazole (Sporanox, Tolsura) | can increase the risk of side effects of Ingrezza |
| Drugs that slow the activity of the CYP2D6 enzyme | • paroxetine (Paxil, Brisdelle) • quinidine | can increase the risk of side effects of Ingrezza |
| Drugs that speed up the activity of the CYP3A4 enzyme | • carbamazepine (Tegretol, others) • rifampin (Rimactane) | can make Ingrezza less effective |
| Digoxin (Lanoxin) | — | can increase the risk of side effects of digoxin |
Learn more about certain drug interactions that can occur with Ingrezza.
Interaction with drugs that slow the activity of the CYP3A4 enzyme
Ingrezza interacts with drugs that slow the activity of the CYP3A4 enzyme (protein). This enzyme is responsible for breaking down certain drugs.
Examples of drugs that slow the activity of the CYP3A4 enzyme include:
- ketoconazole
- itraconazole (Sporanox, Tolsura)
- clarithromycin
- the HIV drugs ritonavir (Norvir) and cobicistat (Tybost)
What could happen
When you take a dose of Ingrezza, the CYP3A4 enzyme helps break down the drug and remove it from your body. If you also take a drug that slows the activity of this enzyme, Ingrezza won’t be broken down as quickly. This increases the amount of Ingrezza in your system, which raises your risk of side effects from the drug.
What you can do
If you need to take Ingrezza with a drug that slows the activity of the CYP3A4 enzyme, your doctor will likely prescribe a lower Ingrezza dosage for you. They may also monitor you closely for side effects during your treatment.
Interaction with drugs that slow the activity of the CYP2D6 enzyme
Ingrezza interacts with drugs that slow the activity of the CYP2D6 enzyme. This enzyme is responsible for breaking down certain drugs.
Examples of drugs that slow the activity of the CYP2D6 enzyme include:
- paroxetine (Paxil, Brisdelle)
- fluoxetine (Prozac)
- quinidine
- tipranavir (Aptivus)
What could happen
After you take a dose of Ingrezza, the CYP2D6 enzyme helps break down the drug and remove it from your body. If you also take a drug that slows the activity of this enzyme, your body doesn’t break down Ingrezza as quickly as it should. This can cause Ingrezza levels to build up in your body, which raises your risk of side effects from the drug.
What you can do
If you need to take Ingrezza with a drug that slows the activity of CYP2D6, your doctor will likely prescribe a lower dosage of Ingrezza for you. They may also monitor you closely for side effects while you’re taking Ingrezza.
Interaction with drugs that speed up the CYP3A4 enzyme
Ingrezza interacts with drugs that speed up the activity of the CYP3A4 enzyme. This enzyme helps your body break down certain drugs.
Examples of drugs that speed up the activity of CYP3A4 include:
- carbamazepine (Tegretol, others)
- rifampin (Rimactane)
- apalutamide (Erleada)
- primidone (Mysoline)
What could happen
After you take Ingrezza, the CYP3A4 enzyme helps break down the drug and clear it from your body. But if you also take a drug that speeds up the activity of CYP3A4, your body breaks down Ingrezza more quickly than usual. This causes the level of Ingrezza in your body to drop, and the drug may be less effective.
What you can do
Taking Ingrezza with a drug that speeds up the activity of CYP3A4 is not recommended. Instead, your doctor can suggest an alternative to Ingrezza or to the drug that speeds up CYP3A4.
Ingrezza 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 Ingrezza.
Does Ingrezza interact with supplements?
Before you start taking Ingrezza, talk with your doctor and pharmacist about any supplements, herbs, and vitamins 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.
Ingrezza interactions with herbs
Ingrezza interacts with St. John’s wort. This herbal supplement is used to ease symptoms of depression and other conditions.
St. John’s wort speeds up the activity of the CYP3A4* enzyme (protein). If you take St. John’s wort with Ingrezza, your body breaks down Ingrezza more quickly than usual. This causes the level of Ingrezza in your system to drop, which could make the drug less effective.
Before you begin treatment with Ingrezza, tell your doctor whether you take St. John’s wort. Your doctor will likely suggest that you don’t take the two together. They can recommend an alternative to St. John’s wort or Ingrezza instead.
* To learn more about Ingrezza and CYP3A4, see the “Drug interactions explained” section above.
Ingrezza and vitamins
There are currently no reports of Ingrezza interacting with vitamins. But this doesn’t mean that vitamin interactions won’t be recognized in the future.
For this reason, it’s still important to check with your doctor or pharmacist before taking any of these products while using Ingrezza.
Does Ingrezza interact with food?
Ingrezza interacts with grapefruit and grapefruit juice.
Grapefruit and grapefruit juice can raise your risk of side effects from taking Ingrezza. This is because grapefruit products slow the activity of the CYP3A4 enzyme. This can raise the level of Ingrezza in your body, raising your risk of side effects.
Due to this interaction, your doctor may suggest that you do not consume grapefruit or grapefruit juice while you’re taking Ingrezza.
If you have other questions about Ingrezza and possible food interactions, talk with your doctor or pharmacist.
Does Ingrezza interact with vaccines?
Ingrezza isn’t known to interact with any vaccines.
Talk with your doctor or pharmacist if you have questions about receiving vaccines while taking Ingrezza.
Does Ingrezza interact with lab tests?
Ingrezza isn’t known to interact with any lab tests.
Talk with your doctor if you have questions about receiving lab work while taking Ingrezza.
Does Ingrezza interact with cannabis or CBD?There are currently no reports of Ingrezza 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 Ingrezza.
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 Ingrezza. Before taking Ingrezza, talk with your doctor about your health history. They’ll determine whether Ingrezza is right for you.
Health conditions or other factors that might interact with Ingrezza include:
Heart disease. Before taking Ingrezza, tell your doctor if you have heart disease, such as heart failure, or if you’ve had a heart attack. Having heart disease can raise your risk of long QT syndrome, a rare but serious side effect Ingrezza may cause.
Irregular heart rhythm. If you have an irregular heart rhythm (including a heart arrhythmia), your doctor will determine whether Ingrezza is safe for you to take. Having an existing irregular heart rhythm raises your risk of long QT syndrome.
Liver condition. Before taking Ingrezza, it’s important to tell your doctor if you have a liver condition, such as fatty liver disease. Depending on how severe your liver problem is, your doctor may prescribe a lower dose of Ingrezza for you.
Pregnancy. It’s not known whether it’s safe to take Ingrezza while pregnant. If you’re pregnant or planning a pregnancy, talk with your doctor to learn more about the risks and benefits of taking Ingrezza during pregnancy.
Breastfeeding. It’s not known whether it’s safe to take Ingrezza while breastfeeding. If you’re breastfeeding or planning to do so, talk with your doctor before starting Ingrezza treatment.
Allergic reaction. If you’ve had an allergic reaction to Ingrezza or any of its ingredients, your doctor will likely not prescribe Ingrezza. This is because taking the drug could cause another allergic reaction. You can ask your doctor about other treatments that may be better choices for you.
Taking certain steps can help you avoid interactions with Ingrezza. 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 Ingrezza treatment.
It’s also important to understand Ingrezza’s
If you have trouble reading or understanding this information, your doctor or pharmacist can help.
Taking Ingrezza exactly as prescribed can also help prevent interactions.
If you still have questions about Ingrezza and its possible interactions, talk with your doctor.
Questions you may want to ask your doctor include:
- Does my Ingrezza dosage affect my risk of interactions?
- If Ingrezza interacts with a health condition I have, is it still safe for me to take?
- If I start taking a new drug or supplement during Ingrezza treatment, can you check for any interactions?
- Should I let you know about any lifestyle changes I make while taking Ingrezza, such as to my exercise routine or diet?
To learn more about Ingrezza, see these articles:
To get information on different conditions and tips for improving your health, subscribe to any of Healthline’s newsletters. You may also want to check out the online communities at Bezzy. It’s a place where people with certain conditions can find support and connect with others.
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.