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Drug Information

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  • Common uses
  • How to take the medication
  • Common side effects
  • Precautions & interactions

How Venetoclax works, side effects, interactions and precautions.

Venetoclax

Venetoclax

(ven et' oh klax)

Brand Name(s): , Venclexta®


WHY is this medicine prescribed?

Venetoclax is used to treat certain patients with chronic lymphocytic leukemia (CLL; a type of cancer that begins in the white blood cells) who have already been treated with at least one other chemotherapy medication. 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.

Are there OTHER USES for this medicine?

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

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.

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 ([WEB]) or the manufacturer's website to obtain the Medication Guide.

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.
  • tell your doctor if you are taking clarithromycin (Biaxin, in Prevpac), conivaptan (Vaprisol), indinavir (Crixivan), itraconazole (Onmel, Sporanox), ketoconazole, lopinavir (in Kaletra), posaconazole (Noxafil), ritonavir (Norvir, in Kaletra, Technivie, Viekira Pak), or voriconazole (Vfend). Your doctor may tell you not to take venetoclax if you are taking one or more of these medications.
  • tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins and nutritional supplements you are taking or plan to take. Be sure to mention any of the following: amiodarone (Cordarone, Nexterone, Pacerone), azithromycin (Zithromax, Zmax), bosentan (Tracleer), captopril, carbamazepine (Carbatrol, Epitol, Equetro, Tegretol, Teril), carvedilol (Coreg), ciprofloxacin (Cipro), cyclosporine (Gengraf, Neoral, Sandimmune), digoxin (Digitek, Lanoxin), diltiazem (Cardizem, Cartia XT, Diltzac, Taztia, Tiazac), dronedarone (Multaq), efavirenz (Sustiva, in Atripla), erythromycin (E.E.S., Eryc, Eryped, Ery-tab, Erythrocin), etravirine (Intelence), everolimus (Afinitor, Zortress), felodipine, fluconazole (Diflucan), modafinil (Nuvigil, Provigil), nafcillin (Nallpen), phenytoin (Dilantin, Phenytek), quinidine (in Nuedexta), ranolazine (Ranexa), rifampin (Rifadin, Rimactane, in Rifamate, Rifater), sirolimus (Repamune), ticagrelor (Brilinta), verapamil (Calan, Covera-HS, Verelan, in Tarka), or warfarin (Coumadin, Jantoven). Your doctor may need to change the doses of your medications or monitor you carefully for side effects. Many other medications may also interact with venetoclax, so be sure to tell your doctor about all the medications you are taking, even those that do not appear on this list.
  • tell your doctor what herbal products you are taking, especially quercetin, or Saint John's wort.
  • 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, plan to become pregnant, or are breast-feeding. 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 last 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.
  • 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 6-8 glasses (48-64 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.

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
  • swelling of your arms or hands
  • back pain
  • headache
  • runny or stuffy nose
  • dizziness
  • pale skin

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, sore throat, cough, chills, and other signs of infection
  • decreased urination
  • swelling of your legs, ankles, or feet
  • unusual bleeding or bruising

Laboratory animals who were given venetoclax developed problems with their testicles and produced fewer sperm (male reproductive cells) than normal. It is not known if venetoclax will damage the testicles or decrease the number of sperm produced in men. Talk to your doctor about the risks of taking venetoclax if you would like to have children in the future.

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 ([WEB]) or by phone (1-800-332-1088).

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. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website ([WEB]) for more information if you do not have access to a take-back program.

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. [WEB]

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 [WEB]. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

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 with venetoclax to be sure it is safe for you to take venetoclax, and to check your body's response to the medication.

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

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry 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, 2018. The American Society of Health-System Pharmacists, Inc., 4500 East-West Highway, Suite 900, Bethesda, Maryland. All Rights Reserved. Duplication for commercial use must be authorized by ASHP.

Selected Revisions: June 15, 2016.

Venetoclax is commonly used to treat:

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