Class Name(s):

• 10:00 Antineoplastic Agents

Pronunciation:

• (ven et' oh klax)

Brand Name(s):

• Venclexta^®

WHY is this medicine prescribed?

Venetoclax is used alone or in combination with obinutuzumab (Gazyva) or rituximab (Rituxan) to treat certain types of chronic lymphocytic leukemia (CLL; a type of cancer that begins in the white blood cells) or certain types of small lymphocytic lymphoma (SLL; a type of cancer that begins mostly in the lymph nodes). It is also used in combination with either azacitidine (Vidaza), decitabine (Dacogen), or cytarabine as a first treatment for acute myeloid leukemia (AML; a type of cancer that begins in the white blood cells) in people 75 years of age or older, or in adults who have medical conditions that prevents them from being treated with other chemotherapy medications. Venetoclax is in a class of medications called B-cell lymphoma-2 (BCL-2) inhibitors. It works by blocking the action of a certain protein in the body that helps cancer cells survive. This helps to kill cancer cells.

HOW should this medicine be used?

Venetoclax comes as a tablet to take by mouth. It is usually taken with a meal and water once a day. Take venetoclax at around the same time every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take venetoclax exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Swallow the tablets whole; do not split, chew, or crush them.

If you vomit after taking venetoclax, do not repeat the dose. Continue your regular dosing schedule.

Your doctor will probably start you on a low dose of venetoclax and gradually increase your dose, not more than once every week for the first 5 weeks if you are being treated for CLL or SLL, and once a day for the first 3 or 4 days if you are being treated for AML.

Your doctor may need to interrupt or stop your treatment if you experience certain side effects. Be sure to tell your doctor how you are feeling during your treatment with venetoclax. For certain side effects, your doctor may tell you to start taking venetoclax at a lower dose.

Your doctor or pharmacist will give you the manufacturer's patient information sheet (Medication Guide) when you begin treatment with venetoclax and each time you refill your prescription. Read the information carefully and ask your doctor or pharmacist if you have any questions. You can also visit the Food and Drug Administration (FDA) website (http://www.fda.gov/Drugs/DrugSafety/ucm085729.htm) or the manufacturer's website to obtain the Medication Guide.

Are there OTHER USES for this medication?

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

What SPECIAL PRECAUTIONS should I follow?

Before taking venetoclax,

• tell your doctor and pharmacist if you are allergic to venetoclax, any other medications, or any of the ingredients in venetoclax tablets. Ask your pharmacist or check the Medication Guide for a list of the ingredients.
• some medications should not be taken with venetoclax. Other medications may cause dosing changes or extra monitoring when taken with venetoclax. Make sure you have discussed any medications you are currently taking or plan to take before starting venetoclax with your doctor and pharmacist. Before starting, stopping, or changing any medications while taking venetoclax, please get the advice of your doctor or pharmacist.
• the following herbal product may interact with venetoclax: St. John's wort. Be sure to let your doctor and pharmacist know that you are taking this medication before you start taking venetoclax. Do not start this medication while taking venetoclax without discussing with your healthcare provider.
• tell your doctor if you have or have ever had problems with your levels of potassium, phosphorus, or calcium in your blood; high levels of uric acid in your blood; gout (a type of arthritis caused by crystals deposited in the joints); or kidney or liver disease.
• tell your doctor if you are pregnant or plan to become pregnant. If you can become pregnant, you will need to have a pregnancy test before beginning treatment with venetoclax. You should not become pregnant during your treatment and for 30 days after your final dose. Talk to your doctor about birth control methods that you can use during your treatment. If you become pregnant while taking venetoclax, call your doctor.
• tell your doctor if you are breastfeeding. Do not breastfeed while taking venetoclax and for 1 week after your last dose.
• you should know that this medication may decrease fertility in men. Talk to your doctor about the risks of taking venetoclax.
• do not have any vaccinations before, during, or after treatment with venetoclax without talking to your doctor.
• you should know that you may experience tumor lysis syndrome (TLS; a condition caused by the fast breakdown of cancer cells that can cause kidney failure and other complications) during your treatment with venetoclax. This is more likely to happen when you are first starting treatment, and each time your dose is increased. To help reduce your risk of experiencing TLS you should drink at least 6 to 8 glasses (48 to 64 ounces) of water a day for 2 days before and on the day of your first dose, and each time your dose is increased. In addition your doctor will give you a medication to take before starting and during your treatment to help prevent this side effect. If you experience any of the following symptoms of TLS call your doctor immediately: fever, chills, nausea, vomiting, confusion, shortness of breath, seizures, irregular heartbeat, dark or cloudy urine, unusual tiredness, or muscle or joint pain.

What SPECIAL DIETARY instructions should I follow?

Do not eat grapefruit, starfruit, or Seville oranges (sometimes used in marmalades), or drink grapefruit juice while taking this medication.

What should I do IF I FORGET to take a dose?

If you remember the missed dose within 8 hours of the time you were scheduled to take it, take the missed dose right away. However, if more than 8 hours have passed since the time you usually take venetoclax, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

If you miss taking venetoclax for more than 7 days, you should call your doctor before taking any more medication. Your doctor may want to restart your medication at a lower dose.

What SIDE EFFECTS can this medicine cause?

Venetoclax may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

• diarrhea
• constipation
• nausea
• vomiting
• decreased appetite
• extreme tiredness
• swelling of your arms or hands
• back pain
• bone, muscle, or joint pain
• abdominal pain
• swelling or sores in the mouth
• mouth or throat pain
• headache
• runny or stuffy nose, cough
• shortness of breath
• dizziness
• rash
• difficulty falling asleep or staying asleep

Some side effects can be serious. If you experience any of these symptoms or those listed in the SPECIAL PRECAUTIONS section, call your doctor immediately:

• fever alone or along with sore throat, cough, chills, warm, red, painful or swollen skin, urgent, frequent, or painful urination, and other signs of infection
• decreased urination
• swelling of your legs, ankles, or feet
• unusual or heavy bleeding or bruising
• pale skin, shortness of breath, dizziness, extreme tiredness, fast heartbeat

Venetoclax may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

What should I do in case of OVERDOSE?

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at http://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

What should I know about STORAGE and DISPOSAL of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Do not transfer the medication to a different container. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

Keep all medication out of sight and reach of children as many containers are not child-resistant. Always lock safety caps. Place the medication in a safe location - one that is up and away and out of their sight and reach. http://www.upandaway.org

Dispose of unneeded medications in a way so that pets, children, and other people cannot take them. Do not flush this medication down the toilet. Use a medicine take-back program. Talk to your pharmacist about take-back programs in your community. Visit the FDA's Safe Disposal of Medicines website http://goo.gl/c4Rm4p for more information.

What OTHER INFORMATION should I know?

Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests before and during your treatment to check your body's response to venetoclax.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

Keep a written list of all of the prescription and nonprescription (over-the-counter) medicines, vitamins, minerals, and dietary supplements you are taking. Bring this list with you each time you visit a doctor or if you are admitted to the hospital. You should carry the list with you in case of emergencies.

This report on medications is for your information only, and is not considered individual patient advice. Because of the changing nature of drug information, please consult your physician or pharmacist about specific clinical use.

The American Society of Health-System Pharmacists, Inc. represents that the information provided hereunder was formulated with a reasonable standard of care, and in conformity with professional standards in the field. The American Society of Health-System Pharmacists, Inc. makes no representations or warranties, express or implied, including, but not limited to, any implied warranty of merchantability and/or fitness for a particular purpose, with respect to such information and specifically disclaims all such warranties. Users are advised that decisions regarding drug therapy are complex medical decisions requiring the independent, informed decision of an appropriate health care professional, and the information is provided for informational purposes only. The entire monograph for a drug should be reviewed for a thorough understanding of the drug's actions, uses and side effects. The American Society of Health-System Pharmacists, Inc. does not endorse or recommend the use of any drug. The information is not a substitute for medical care.

AHFS^® Patient Medication Information™ Copyright, 2025. The American Society of Health-System Pharmacists^®, 4500 East-West Highway, Suite 900, Bethesda, Maryland. All Rights Reserved. Duplication for commercial use must be authorized by ASHP.

Selected Revisions: January 15, 2021.