If you have cancer, your doctor may prescribe Venclexta for you.

It’s a prescription drug used to treat specific cancers in adults in certain situations. These cancers include:

To learn more about AML, SLL, and CLL, and how Venclexta is used to treat them, see the “What is Venclexta used for?” section below.

Venclexta basics

Venclexta comes as tablets that you’ll take by mouth. It’s a type of targeted cancer therapy.

Venclexta contains the active drug venetoclax. But the drug isn’t available as generic venetoclax tablets.

Read on to learn about Venclexta’s side effects, uses, and more.

Like most drugs, Venclexta may cause mild or serious side effects. The lists below describe some of the more common side effects it may cause. These lists don’t include all possible side effects.

Keep in mind that side effects of a drug can depend on:

  • your age
  • other health conditions you have
  • other medications you take
  • the condition you’re using the drug to treat

Your doctor or pharmacist can tell you more about the potential side effects of Venclexta. They can also suggest ways to help reduce these side effects.

Mild side effects

Here’s a list of some of the mild side effects that Venclexta can cause. To learn about other mild side effects, talk with your doctor or pharmacist, or read Venclexta’s medication guide.

Mild side effects of Venclexta that have been reported include:

Mild side effects of many drugs may go away within a few days or a couple of weeks. But if they become bothersome, talk with your doctor or pharmacist.

* For more information about this side effect, see the “Side effect focus” section below.

Serious side effects

Serious side effects from Venclexta can occur, but they aren’t common. If you have serious side effects from Venclexta, call your doctor right away. However, if you think you’re having a medical emergency, you should call 911 or your local emergency number.

Serious side effects of Venclexta that have been reported include:

* For more information about this side effect, see the “Side effect focus” section below.

Side effect focus

Learn more about some of the side effects Venclexta may cause.

Tumor lysis syndrome

You may have tumor lysis syndrome (TLS) while you’re taking Venclexta. This was a rare but serious side effect in studies of the drug.

TLS happens when cancer cells in your body break down and release their contents into your blood. The cancer cells release chemicals such as phosphate, potassium, calcium, and uric acid.

TLS can lead to kidney failure. In some cases, it may be life threatening.

Symptoms of TLS can include:

What might help

Tell your doctor if you develop any symptoms of TLS while you’re taking Venclexta.

While you’re taking Venclexta, your doctor may give you medications to help prevent TLS. They’ll also order tests often to monitor for TLS.

It’s important to stay hydrated by drinking lots of water while you take Venclexta. This can lower your risk for TLS by helping your kidneys to remove chemicals from your body quickly.

Problems with digestion

You may have problems with digestion during Venclexta treatment. These side effects were common in studies of the drug.

Examples of digestion problems you may have with Venclexta include:

What might help

Tell your doctor if you have any bothersome digestive symptoms while you’re taking Venclexta.

They can suggest ways to ease your symptoms. This could include having you take certain over-the-counter drugs. But it’s important to talk with your doctor before taking any other medications with Venclexta.

Abnormal bleeding

It’s possible to have abnormal bleeding while you’re taking Venclexta. This was a common side effect in studies of the drug.

While you’re taking Venclexta, you may have unusual bleeding from your:

You could also have blood in your urine.

What might help

Tell your doctor about any abnormal or unusual bleeding you have while you’re taking Venclexta.

Your doctor can check to make sure your bleeding isn’t a sign of a more serious condition. And they’ll suggest ways to manage this side effect.

Allergic reaction

Some people may have an allergic reaction to Venclexta. While allergic reaction wasn’t reported in studies of Venclexta, it can still happen.

Symptoms of a mild allergic reaction can include:

  • skin rash
  • itchiness
  • flushing (temporary warmth, redness, or deepening of skin color)

A more severe allergic reaction is rare but possible. Symptoms of a severe allergic reaction can include swelling under your skin, typically in your eyelids, lips, hands, or feet. They can also include swelling of your tongue, mouth, or throat, which can cause trouble breathing.

Call your doctor right away if you have an allergic reaction to Venclexta. But if you think you’re having a medical emergency, call 911 or your local emergency number.

Costs of prescription drugs can vary depending on many factors. These factors include what your insurance plan covers and which pharmacy you use. To find current prices for Venclexta in your area, visit WellRx.com.

If you have questions about how to pay for your prescription, talk with your doctor or pharmacist. You can also visit the Venclexta manufacturer’s website to see if they have support options.

Find answers below to some commonly asked questions about Venclexta.

Is Venclexta used for multiple myeloma, MDS, or MCL?

Venclexta isn’t approved to treat multiple myeloma, myelodysplastic syndromes (MDS), or mantle cell lymphoma (MCL). But the drug may sometimes be used off-label for these cancers. (Off-label use means using a drug for a condition other than the one it’s approved to treat.)

Multiple myeloma is a type of cancer that affects plasma cells, which are a type of white blood cell. MDS is a group of cancers that affect blood cells in the bone marrow. And MCL is another cancer that affects white blood cells.

If you have questions about using Venclexta to treat multiple myeloma, MDS, or MCL, talk with your doctor.

How does Venclexta work?

Venclexta is used to treat the following cancers:

AML, SLL, and CLL affect cells in your blood and bone marrow. These cancers have high levels of a protein called BCL-2.

BCL-2 keeps cancer cells from destroying themselves, allowing them to build up in your body. Venclexta’s mechanism of action (how it works) is to block BCL-2. By blocking this protein, Venclexta causes the cancer cells to die.

If you have more questions about how Venclexta works, talk with your doctor.

Is Venclexta a chemotherapy drug?

No, Venclexta isn’t a chemotherapy drug. Instead, it’s a type of targeted therapy.

Chemotherapy works by killing cells in your body that quickly multiply (make more cells). Cancer cells generally multiply more quickly than healthy cells do. But some healthy cells also multiply quickly. So, chemotherapy can affect both cancer cells and healthy cells.

Venclexta works differently than chemotherapy. It targets a protein found in cancer cells called BCL-2. For details about how it works, see “How does Venclexta work?” just above.

How effective is Venclexta?

In studies, Venclexta was effective in treating acute myeloid leukemia (AML), small lymphocytic lymphoma (SLL), and chronic lymphocytic leukemia (CLL).

To learn how Venclexta performed in studies, see the drug’s prescribing information. If you have questions about how effective Venclexta is for your condition, talk with your doctor.

Are any reviews available from people who’ve used Venclexta?

Yes, there are reviews available from people who’ve used Venclexta for certain cancers.

Venclexta is used in certain situations to treat the following cancers:

To learn about people’s experiences with Venclexta for CLL, visit this page or this page.

The drug’s manufacturer hasn’t provided reviews from people who’ve taken their drug for AML or SLL. Your doctor can provide more information about what to expect with Venclexta when it’s used for these purposes.

If you have cancer, your doctor may prescribe Venclexta for you. Cancer happens when cells in your body grow very quickly and out of control.

Venclexta is prescribed for adults and used in certain situations for these cancers:

  • Acute myeloid leukemia (AML). With AML, your myeloid cells grow abnormally. (These cells are found in your bone marrow, which is the spongy tissue inside your bones.) The abnormal myeloid cells build up in your body and replace healthy cells. For this purpose, Venclexta is used:
    • for AML that’s newly diagnosed
    • together with other cancer drugs, including azacitidine (Onureg, Vidaza), decitabine (Dacogen), and cytarabine
    • in adults ages 75 years and older, or in adults of any age who can’t take chemotherapy
  • Small lymphocytic lymphoma (SLL) or chronic lymphocytic leukemia (CLL). With SLL and CLL, cancer affects your B cells. (These are a type of white blood cell.) For SLL, the cancer cells are mostly found in your lymph nodes. For CLL, the cancer cells are mostly found in your bone marrow and blood. For SLL or CLL, Venclexta is used in adults of any age.

Venclexta works by blocking a certain protein in your body. This causes cancer cells to die. To learn more about how the drug works, see the “What are some frequently asked questions about Venclexta?” section above.

Your doctor will recommend the dosage of Venclexta that’s right for you. Below are commonly used dosages, but always take the dosage your doctor prescribes.

Form and strengths

Venclexta comes as tablets that you’ll take by mouth.

It’s available in the following strengths:

  • 10 milligrams (mg)
  • 50 mg
  • 100 mg

Recommended dosages

Your Venclexta dosage depends on:

  • how well your condition is improving with Venclexta treatment
  • other health conditions you have
  • other medications you take

Venclexta dosages also vary depending on whether it’s treating:

Your doctor will tell you how long you’ll need to take Venclexta for these conditions. General dosages are described below. To view full details about Venclexta’s dosages, check out the drug’s prescribing information.

Venclexta’s AML dosing

The dosing schedule for AML follows a 28-day treatment cycle.

During the first treatment cycle, the daily dose changes over the first 3 days. It includes daily doses of 100 mg, 200 mg, and 400 mg. Then on day four and after, you’ll take either 400 mg daily or 600 mg daily.

Venclexta’s SLL or CLL dosing

The dosing schedules for SLL and CLL are set up by treatment weeks.

During the first four weeks, your daily dosage will increase each week. Then at week five, you’ll start taking 400 mg daily.

Questions about Venclexta’s dosage

Here are some common questions about taking Venclexta.

  • What if I miss a dose of Venclexta? If it’s less than 8 hours since your missed dose was due, take the missed dose as soon as you remember. Then you’ll take your next dose at its usual time. But if it’s more than 8 hours since your missed dose was due, skip the missed dose. Then, you’ll take your next dose at its usual time. If you aren’t sure whether to take a missed dose or skip it, talk with your doctor or pharmacist.
  • Will I need to use Venclexta long term? How long should I take Venclexta? You might take Venclexta long term. The length of time you’ll take this drug depends on a few factors. These include the condition you’re using it to treat and other medications you’re taking with it. Your doctor will tell you how long you’ll need to take Venclexta.
  • How long does Venclexta take to work? Venclexta starts working to treat your condition right after you take your first dose. But you probably won’t notice that it’s working in your body. Your doctor will order certain tests to make sure Venclexta is working for you.

Your doctor will explain how you should take Venclexta. They’ll also explain how much to take and how often. Be sure to follow your doctor’s instructions.

Taking Venclexta

You’ll take Venclexta tablets by mouth once each day.

Try to take your doses at the same time each day. This keeps a steady level of Venclexta in your system, helping the drug work at its best.

Taking Venclexta with other drugs

Your doctor may have you take Venclexta together with other cancer drugs. This helps treat your cancer more effectively.

Whether your doctor prescribes other cancer treatments depends on the specific type of cancer you’re using Venclexta to treat.

Examples of other drugs your doctor may prescribe with Venclexta include:

If you have questions about using Venclexta with other medications, talk with your doctor.

Questions about taking Venclexta

Below are answers to a few questions about taking Venclexta.

  • Can Venclexta be chewed, crushed, or split? No, you should not chew, crush, or split Venclexta tablets. Instead, you should swallow the tablets whole. If you have trouble swallowing Venclexta, talk with your doctor or pharmacist. And check out this list of tips for swallowing pills.
  • Should I take Venclexta with food? Yes, you should take each dose of Venclexta with a meal and with water.
Questions for your doctor

You may have questions about Venclexta and your treatment plan. It’s important to discuss all your concerns with your doctor.

Here are a few tips that might help guide your discussion:

  • Before your appointment, write down questions such as:
    • How will Venclexta affect my body, mood, or lifestyle?
  • Bring someone with you to your appointment if doing so will help you feel more comfortable.
  • If you don’t understand something related to your condition or treatment, ask your doctor to explain it to you.

Remember, your doctor and other healthcare professionals are available to help you. And they want you to get the best care possible. So, don’t be afraid to ask questions or offer feedback on your treatment.

Some important things to discuss with your doctor when considering Venclexta treatment include:

  • any medical conditions you have
  • any drugs you take
  • your overall health

These considerations and others are described in more detail below.

Interactions

Taking a medication with certain vaccines, foods, and other things can affect how the medication works. These effects are called interactions.

Before taking Venclexta, be sure to tell your doctor about all medications you take, including prescription and over-the-counter types. Also describe any vitamins, herbs, or supplements you use. Your doctor or pharmacist can tell you about any interactions they may have with Venclexta.

Interactions with drugs or supplements

Venclexta can interact with several types of drugs, including:

This list does not contain all types of drugs that may interact with Venclexta. Your doctor or pharmacist can tell you more about these interactions and any others that may occur with the use of Venclexta.

Other interactions

You should not get live vaccines while taking Venclexta. Live vaccines contain a weakened but live form of the bacteria or virus they’re meant to prevent an infection from.

Typically, live vaccines don’t cause an infection in a person with a healthy immune system. But a live vaccine could cause an infection in a person with a weakened immune system. This includes someone taking Venclexta.

Examples of live vaccines include:

Talk with your doctor about whether you’re up to date on all recommended vaccines before starting Venclexta. They’ll advise you when it’s safe to receive a vaccine.

Warnings

Venclexta may not be right for you if you have certain medical conditions or other factors that affect your health. Talk with your doctor about your health history before you take Venclexta. Factors to consider include those in the list below.

  • Problems with your electrolyte or uric acid levels. Tell your doctor if you have abnormal levels of uric acid or electrolytes in your blood. Venclexta may cause tumor lysis syndrome (TLS) as a side effect. And TLS can cause abnormal levels of uric acid and electrolytes, including potassium and calcium. (For details on TLS, see the “Side effect focus” section in “What are Venclexta’s side effects?” above.) Your doctor may want to correct the level of these substances in your blood before you start taking Venclexta.
  • Kidney problems. Before starting Venclexta, tell your doctor if you have kidney problems. This condition could increase your risk for tumor lysis syndrome (TLS) with Venclexta. (For details on TLS, see the “Side effect focus” section in “What are Venclexta’s side effects?” above.)
  • Severe liver problems. If you have severe liver problems, your doctor may prescribe a dosage of Venclexta for you that’s lower than usual. Be sure to tell your doctor about any liver problems you have before starting Venclexta.
  • Allergic reaction. If you’ve had an allergic reaction to Venclexta or any of its ingredients, you should not take Venclexta. Ask your doctor what other medications are better options for you.

Venclexta and alcohol

There aren’t any known interactions between Venclexta and alcohol.

If you drink alcohol, talk with your doctor about an amount that’s safe for you to drink while you’re taking Venclexta.

Pregnancy and breastfeeding

It may not be safe to take Venclexta during pregnancy or while breastfeeding.

If you’re able to become pregnant, your doctor will check to make sure you have a negative pregnancy test before starting this drug. They’ll recommend that you use effective birth control during treatment and for at least 30 days after your last dose.

It’s best to avoid breastfeeding while you’re taking the drug and for at least 1 week after your last dose.

To learn more about the effects of Venclexta on pregnancy and breastfeeding, talk with your doctor.

Both Venclexta and Imbruvica are approved to treat small lymphocytic lymphoma (SLL) and chronic lymphocytic leukemia (CLL).

Venclexta is also approved to treat acute myeloid leukemia (AML). But Imbruvica isn’t approved for this use.

To learn more about how Venclexta compares with Imbruvica, see this article. Talk with your doctor if you have questions about which drug is right for you.

Do not take more Venclexta than your doctor prescribes. Doing so can lead to serious side effects.

What to do in case you take too much Venclexta

Call your doctor if you think you’ve taken too much Venclexta. You can also call 800-222-1222 to reach the American Association of Poison Control Centers or use its online resource. However, if you have severe symptoms, immediately call 911 or your local emergency number. Or go to the nearest emergency room.

If you have cancer, your doctor may prescribe Venclexta for you.

If you have questions about using Venclexta, talk with your doctor or pharmacist. You may want to ask about other cancer treatments as well.

Here are a few resources that could be helpful in your decision making:

And here are a few questions you can ask your doctor about Venclexta:

  • Will Venclexta interact with any medications I’m taking?
  • What other cancer treatments should I take with Venclexta?
  • Will my cancer come back after I stop using Venclexta?

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.