Kisqali (ribociclib) is a brand-name oral tablet that’s prescribed for certain types of breast cancer in adults. Kisqali has interactions with some other drugs and certain supplements. Examples include midazolam (Seizalam) and ondansetron.

An interaction occurs when one substance causes another substance to have a different effect than expected.

To learn more about Kisqali’s interactions, keep reading. For additional information about Kisqali, including details about its uses, see this article.

Before you start treatment with Kisqali, tell your doctor and pharmacist which prescription, over-the-counter, and other medications you take. By sharing this information with them, you may help prevent possible interactions. (To learn whether Kisqali interacts with supplements, herbs, or vitamins, see the “Kisqali and other interactions” section below.)

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

Here’s a table of drugs that can interact with Kisqali. Keep in mind that this table doesn’t include all drugs that may interact with Kisqali. Some of these interactions are described in detail just below in “Drug interactions in depth.”

Drug class or drug nameDrug examplesInteraction result with Kisqali
certain benzodiazepines*• alprazolam (Xanax, Xanax XR)
• clonazepam (Klonopin)
• clorazepate (Tranxene)
diazepam (Valium)
• midazolam (Seizalam)
can increase the risk of side effects from the benzodiazepine
certain antibiotics• ciprofloxacin (Cipro)
• clarithromycin
• moxifloxacin
• rifampin (Rifadin, Rifamycin)
can increase the risk of side effects from Kisqali† or the antibiotic, or make Kisqali less effective
certain seizure drugs• carbamazepine (Carbatrol, Equestro, others)
• phenytoin (Dilantin, Phenytek)
• phenobarbital (Sezaby)
can make Kisqai less effective
certain antifungals• itraconazole (Sporanox, Tolsura)
• ketoconazole
• posaconazole (Noxafil)
• voriconazole (Vfend)
can increase the risk of side effects from Kisqali† and the antifungal
certain antidepressants*• citalopram (Celexa)
• nefazodone
• sertraline (Zoloft)
• trazodone
• venlafaxine (Effexor XR)
can increase the risk of side effects from Kisqali† and the antidepressant
certain antivirals• darunavir (Prezista)
• nelfinavir (Viracept)
• ritonavir (Norvir)
can increase the risk of side effects from Kisqali† and the antiviral
antiarrhythmics• amiodarone (Nexterone, Pacerone)
• disopyramide (Norpace, Norpace CR)
• dronedarone (Multaq)
• procainamide
• sotalol (Betapace, Sotilyze, others)
can increase the risk of long QT syndrome and other side effects from the antiarrhythmic
antipsychotics• aripiprazole (Abilify, Aristada, others)
• brexpiprazole (Rexulti)
• clozapine (Clozaril, Versacloz)
• haloperidol (Haldol)
• risperidone (Risperdal, Uzedy, others)
can increase the risk of long QT syndrome
ondansetron*can increase the risk of long QT syndrome and other side effects from ondansetron
buspironecan increase the risk of side effects from buspirone

* For details about this interaction, see the “Drug interactions in depth” section below.
To learn about Kisqali’s side effects, see this article.

There aren’t any known interactions between Kisqali and alcohol. However, your doctor may advise you to avoid or limit alcohol consumption during Kisqali treatment.

This is because consuming large amounts of alcohol can cause liver problems. Kisqali may also cause liver problems as a side effect. This means that drinking alcohol during Kisqali treatment may increase the risk of liver problems.

In addition, drinking alcohol while taking the drug may worsen some of Kisqali’s side effects. For example, you may have worsened headache or fatigue.

If you have questions about limiting alcohol while taking Kisqali, talk with your doctor.

Here’s a closer look at certain drug interactions of Kisqali.

Certain benzodiazepines

Benzodiazepines are prescribed for conditions that include seizures and anxiety.

Interaction result: Taking Kisqali with certain benzodiazepines can increase the risk of side effects from the benzodiazepine.

Interaction explained: Kisqali may slow down the activity of an enzyme (protein) that helps break down certain benzodiazepines in your body. Taking these drugs together could result in a high level of the benzodiazepine in your system. This could increase your risk of side effects from the benzodiazepine.

Examples of benzodiazepine drugs: Here are some benzodiazepines that may interact with Kisqali:

  • alprazolam (Xanax, Xanax XR)
  • clonazepam (Klonopin)
  • clorazepate (Tranxene)
  • diazepam (Valium)
  • midazolam (Seizalam)

Steps you or your doctor may take: Before you take Kisqali, tell your doctor about any benzodiazepines you’re prescribed. They’ll recommend whether it’s safe to take these drugs together. Your doctor may recommend a different benzodiazepine that isn’t known to interact with Kisqali.

If your doctor prescribes Kisqali with a benzodiazepine it interacts with, they may give you a lower dosage of the benzodiazepine. Doing so will help reduce the risk of side effects from the drug.

To learn more about Kisqali and benzodiazepines, talk with your doctor or pharmacist.

Certain antidepressants

Antidepressants are prescribed for depression and other mental health conditions.

Interaction result: Taking Kisqali with certain antidepressants may increase the risk of side effects from either drug. This includes a side effect of long QT syndrome (a type of abnormal heart rhythm).

Interaction explained: Kisqali may slow down the activity of an enzyme (protein) in your body that helps break down certain antidepressants. Likewise, certain antidepressants may slow the activity of an enzyme that helps break down Kisqali. These effects may lead to a high level of either drug in your system, increasing your risk of side effects from Kisqali or the antidepressant.

Examples of antidepressant drugs: Here are some antidepressants that may interact with Kisqali:

Steps you or your doctor may take: Before starting treatment with Kisqali, tell your doctor if you’re taking an antidepressant. They’ll advise you on whether it’s safe to take these medications together. Your doctor may recommend a different antidepressant that isn’t known to interact with Kisqali.

In some cases, your doctor may still prescribe Kisqali with an antidepressant it interacts with. To reduce the risk of side effects from either drug, your doctor may prescribe a lower dosage of the antidepressant or Kisqali than is typical.

To learn more about Kisqali and antidepressants, talk with your doctor or pharmacist.

Ondansetron

Ondansetron is prescribed to help prevent nausea and vomiting in certain situations. This includes nausea and vomiting related to certain cancer treatments.

Interaction result: Taking Kisqali with ondansetron may increase the risk of side effects, including long QT syndrome, from either drug.

Interaction explained: Both Kisqali and ondansetron may cause long QT syndrome when taken individually. Taking these medications together may further increase this risk.

In addition, Kisqali may slow down the activity of an enzyme in your body that helps break down ondansetron. This may lead to a high level of ondansetron in your system, increasing your risk of other side effects from the drug.

Steps you or your doctor may take: Due to this risk, doctors are unlikely to prescribe Kisqali with ondansetron. They can recommend other ways to help prevent or manage nausea and vomiting with Kisqali.

To learn more about Kisqali and ondansetron, talk with your doctor or pharmacist.

Kisqali may have other interactions, such as with supplements, foods, vaccines, or even lab tests. You’ll find details below. Keep in mind that the following information does not include all other possible interactions with Kisqali.

Kisqali interactions with supplements

Before you start treatment with Kisqali, tell your doctor and pharmacist which supplements, herbs, and vitamins you take. By sharing this information with them, you may help prevent possible interactions.

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

Kisqali interactions with herbs

Doctors will typically recommend that you avoid taking St. John’s wort with Kisqali. St. John’s wort is an herbal supplement that may be used to ease symptoms of depression and other conditions.

St. John’s wort may speed up the activity of an enzyme (protein) in your body that helps break down Kisqali. This may lead to a low level of Kisqali in your system, meaning the drug may not work as well to treat your condition.

Your doctor can suggest treatment options other than St. John’s wort.

Kisqali and vitamins

There are no specific reports of vitamins interacting with Kisqali. However, that doesn’t mean vitamin interactions won’t occur or be recognized in the future. Because of this, you should talk with your doctor or pharmacist before taking any vitamin product with Kisqali.

Kisqali interactions with food

Kisqali can interact with grapefruit and grapefruit juice. This is because grapefruit products can slow the breakdown of Kisqali in your body. This could raise the level of Kisqali in your system, which increases your risk of side effects from Kisqali.

Due to this risk, your doctor may recommend not consuming grapefruit and grapefruit juice while you’re taking Kisqali.

Kisqali and vaccines

There are no specific reports of vaccines interacting with Kisqali. Talk with your doctor or pharmacist to see whether you’re due for any vaccines.

Kisqali and lab tests

There are no specific reports of lab tests interacting with Kisqali. If you have concerns about this medication interacting with lab tests, talk with your doctor.

KISQALI INTERACTION WITH CANNABIS OR CBD

Cannabis (often called marijuana) and cannabis products, such as cannabidiol (CBD), have been reported to interact with Kisqali. Taking Kisqali with cannabis products could increase your risk of side effects from cannabis.

Before you start treatment with Kisqali, tell your doctor and pharmacist if you use cannabis. By sharing this information with them, you may help prevent possible interactions.

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

Certain medical conditions and other factors may increase the risk of interactions with Kisqali. Before you take this drug, be sure to talk with your doctor about your health history. Kisqali may not be the right treatment option if you have certain medical conditions or other factors affecting your health.

Health conditions or factors that might interact with Kisqali include:

  • Liver or kidney problems: If you have a liver or kidney problem, talk with your doctor before taking Kisqali. Examples include liver failure and kidney failure. Having a liver or kidney problem may increase your risk of side effects from Kisqali. To reduce this risk, your doctor may prescribe a lower Kisqali dosage than is typical.
  • Heart problems or related factors: Kisqali may cause long QT syndrome (a type of abnormal heart rhythm) as a side effect. This risk may be increased for people with certain heart problems and related factors. Examples include heart failure, a recent heart attack, and electrolyte imbalance. Your doctor can recommend whether Kisqali is a safe treatment option.
  • Allergic reaction: If you’ve had an allergic reaction to Kisqali or any of its ingredients, your doctor will likely not prescribe Kisqali. Taking the drug could cause another allergic reaction. You can ask them about other treatments that may be better choices for you.
  • Breastfeeding: It’s not known whether it’s safe to use Kisqali while breastfeeding. There isn’t enough information to determine whether the drug passes into breast milk or what effects Kisqali may have on a child who is breastfed. However, to be safe, your doctor may advise you not to breastfeed during Kisqali treatment and for 3 weeks after your last dose. If you’re breastfeeding or planning to, talk with your doctor before using Kisqali. They can talk with you about treatment options and ways to feed your child.
  • Pregnancy: There haven’t been enough clinical trials to determine whether Kisqali is safe to use while pregnant. Animal studies show that the drug may cause congenital anomalies (commonly known as birth defects). However, it’s important to note that animal studies don’t always indicate what may happen in humans. People who are able to become pregnant and who take Kisqali should use effective birth control during treatment and for at least 3 weeks after the last dose of Kisqali. If you’re pregnant or planning to become pregnant, tell your doctor before starting Kisqali. They can advise you on the right treatment plan for you.

You can take certain steps to help prevent interactions with Kisqali. Your doctor and pharmacist are key resources, so reach out to them before starting treatment. For example, you should plan to do the following:

  • Let them know if you drink alcohol or use cannabis.
  • Tell them about any other medications you take, as well as any supplements, herbs, and vitamins.
  • Create a medication list, which your doctor and pharmacist can help you fill out.

It’s also important to read the Kisqali label and other paperwork that may come with the drug. The label may have colored stickers that mention an interaction. And the paperwork, sometimes called the medication guide or patient package insert, may contain details about interactions.

If Kisqali doesn’t come with paperwork, you can ask your pharmacist to print a copy. If you need help reading or understanding this information, ask your doctor or pharmacist.

You can also help prevent interactions with Kisqali by taking it exactly as your doctor prescribes.

Disclaimer: Medical News Today 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.