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Generic Name: venetoclax (ven ET oh klax)
Brand Name: Venclexta, Venclexta Starting Pack

Medically reviewed by on May 29, 2019 – Written by Cerner Multum

What is venetoclax?

Venetoclax is used to treat chronic lymphocytic leukemia or small lymphocytic leukemia in adults. Venetoclax is used alone or in combination with other cancer medicines to treat these conditions.

Venetoclax is used in combination with azacitidine, decitabine, or cytarabine to treat acute myeloid leukemia. This combination is for use in adults who are 75 years or older, or who cannot use standard chemotherapy due to other medical conditions.

Venetoclax is sometimes given after other treatments have failed.

Venetoclax may also be used for purposes not listed in this medication guide.

Important Information

Tell your doctor about all your current medicines and any you start or stop using. Many drugs can interact, and some drugs should not be used together.

Call your doctor at once if you have a fever, chills, joint or muscle pain, tiredness, confusion, shortness of breath, fast or slow heartbeats, nausea, vomiting, dark or cloudy urine, or a seizure (convulsions).

Drink 6 to 8 full glasses of water each day to help prevent these side effects.

Before taking this medicine

You should not use venetoclax if you are allergic to it.

Some medicines can cause unwanted or dangerous effects when used with venetoclax. Your doctor may need to change your treatment plan if you also use:

  • an antibiotic or antifungal medicine;

  • heart medication; or

  • antiviral medicine to treat hepatitis C or HIV.

Tell your doctor about all medicines you use. Do not start or stop using any medicine without asking your doctor.

Tell your doctor if you have ever had:

  • liver or kidney disease;

  • an electrolyte imbalance (such as low levels of potassium or calcium in your blood);

  • gout, or high levels of uric acid in your blood; or

  • if you are scheduled to receive any vaccine.

You may need to have a negative pregnancy test before starting this treatment.

Do not use venetoclax if you are pregnant. It could harm the unborn baby. Tell your doctor right away if you become pregnant while taking venetoclax. Use effective birth control to prevent pregnancy while you are using venetoclax and for at least 30 days after your last dose.

This medicine may affect fertility (ability to have children) in men. Talk to your doctor if you are concerned about this risk.

You should not breast-feed while using this medicine.

How should I take venetoclax?

Follow all directions on your prescription label and read all medication guides or instruction sheets. Your doctor may occasionally change your dose. Use the medicine exactly as directed.

You may receive your first dose in a hospital or clinic setting to quickly treat any serious side effects.

Take venetoclax with food and water, at the same time each day.

Do not crush, chew, or break a venetoclax tablet. Swallow it whole.

If you vomit shortly after taking venetoclax, do not take another tablet. Wait until the next day to take your medicine at the scheduled time.

To prevent certain side effects, drink 6 to 8 glasses of water daily for 2 days before you start taking venetoclax. Also drink 6 to 8 glasses of water on the day you first take venetoclax, and whenever your dose is changed.

Venetoclax can lower your blood cell counts. Your blood will need to be tested often. Your cancer treatments may be delayed based on the results of these tests.

Do not stop using venetoclax without first asking your doctor.

Store tablets in their original container at room temperature, away from moisture and heat. Do not put venetoclax tablets into a daily pill box.

What happens if I miss a dose?

Use the medicine as soon as you can, but skip the missed dose if you are more than 8 hours late for the dose. Do not use two doses at one time.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking venetoclax?

Do not receive a "live" vaccine while using venetoclax. The vaccine may not work as well during this time, and may not fully protect you from disease. Live vaccines include measles, mumps, rubella (MMR), polio, rotavirus, typhoid, yellow fever, varicella (chickenpox), and zoster (shingles).

Grapefruit and Seville oranges may interact with venetoclax and lead to unwanted side effects. Avoid the use of grapefruit products and orange marmalades.

Venetoclax side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have:

  • signs of pneumonia--cough with yellow or green mucus, stabbing chest pain, wheezing, trouble breathing;

  • low blood cell counts--fever, chills, flu-like symptoms, swollen gums, mouth sores, skin sores, pale or yellowed skin, dark colored urine, confusion or weakness; or

  • signs of tumor cell breakdown--fever, chills, joint or muscle pain, feeling tired or short of breath, fast or slow heartbeats, confusion, nausea, vomiting, dark or cloudy urine, or seizure (convulsions).

Your cancer treatments may be delayed or permanently discontinued if you have certain side effects.

Common side effects may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Venetoclax dosing information

Usual Adult Dose for Leukemia:

Weekly ramp-up schedule over 5 weeks:
Week 1: 20 mg orally once a day
Week 2: 50 mg orally once a day
Week 3: 100 mg orally once a day
Week 4: 200 mg orally once a day
Week 5: 400 mg orally once a day

Start after the patient has completed the 5-week dose ramp-up schedule and has received the 400-mg dose for 7 days: 400 mg orally once a day until disease progression or unacceptable toxicity

-Start rituximab after the patient has completed the 5-week dose ramp-up schedule and has received the 400-mg dose for 7 days.
-Administer rituximab on Day 1 of each 28-day cycle for 6 cycles at 375 mg/m2 IV for Cycle 1 and 500 mg/m2 IV for Cycles 2 through 6.
-Patients should continue the 400 mg orally once daily for 24 months from Cycle 1 Day 1 of rituximab.

-All dose regimens begin with a 5-week ramp-up schedule to gradually reduce tumor burden and decrease risk of tumor lysis syndrome (TLS).
-Patients should be adequately hydrated during the dose-titration phase to reduce the risk of TLS.

Uses: As monotherapy or in combination with rituximab for the treatment of patients with chronic lymphocytic leukemia (CLL) or small lymphocytic lymphoma (SLL), with or without 17p deletion, who have received at least one prior therapy

What other drugs will affect venetoclax?

Sometimes it is not safe to use certain medications at the same time. Some drugs can affect your blood levels of other drugs you take, which may increase side effects or make the medications less effective.

Many drugs can affect venetoclax. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed here. Tell your doctor about all your current medicines and any medicine you start or stop using.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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