VENCLEXTA® (venetoclax)
Safety Information
This page contains important safety information about VENCLEXTA.
Read it before starting treatment and keep it to refer to during your treatment. If you have any concerns, contact your healthcare team.
WHAT SIDE EFFECTS CAN VENCLEXTA CAUSE?
Like all medicines, VENCLEXTA can have side effects and sometimes they can be serious.
It is important to be aware of the potential side effects so you can get help from your healthcare team immediately if needed.
Are there any side effects with VENCLEXTA? (4m 03s)
WHAT IS TUMOUR LYSIS SYNDROME (TLS)?
Tumour Lysis Syndrome (TLS):
The more serious side effects can include Tumour Lysis Syndrome (TLS), low white blood cell count (neutropenia) and infection.
TLS is caused by the rapid breakdown of cancer cells, resulting in high levels of certain chemicals and low levels of calcium circulating in the blood.
This can cause serious damage to the kidneys and other organs in the body and can be fatal.
TLS is most likely to occur in the first weeks of your treatment. TLS can occur within six to eight hours after the first dose and at each dose increase, which is why you need to follow all your doctor's instructions carefully, especially when you start treatment with VENCLEXTA.
Having your blood tested is important to prevent and treat TLS. It is important for you to keep your scheduled appointments for blood tests. The changes in your blood that could lead to TLS may have no symptoms until the situation becomes very serious.
Tell your doctor, nurse or pharmacist if you have or have had kidney problems as this can increase the risk of TLS.
Take any additional medicines your doctor may prescribe to help prevent TLS (if you are at higher risk).
Symptoms of TLS
Contact your doctor immediately or go to the Emergency Department if you notice any of these TLS symptoms:
Fever (≥38°C) or chills
Feeling sick or vomiting
Feeling confused
Convulsions or fits
Dark or cloudy urine
Pain in the muscles or joints
Being short of breath
Changes in your heart rate - slow, fast or irregular
Feeling unusually tired
To help reduce your risk of TLS:
WHAT IS NEUTROPENIA?
Low white blood count (neutropenia) and infection
You may experience a low number of neutrophils (a type of white blood cell) — this can be severe and require treatment. Your doctor will check your blood counts during treatment with VENCLEXTA.
A low white blood cell count can increase your risk of infection.
You may experience infections during treatment with VENCLEXTA. Some infections can be very serious or even fatal.
Call your doctor straight away or go straight to the Emergency Department at your nearest hospital if you notice any of these symptoms:
Fever (≥38°C) or chills
Congestion on the chest
Feeling confused
Cough, runny nose, sore throat
Feeling weak
Pain or burning when passing urine
Your doctor will closely monitor and treat you right away if you have fever or any signs of infection during treatment with VENCLEXTA.
LESS SERIOUS SIDE EFFECTS
Serious side effects
Contact your doctor or go to the Emergency Department immediately if you experience any of the symptoms of TLS or infection – see full symptom lists above.
Less serious side effects
Tell your doctor, nurse or pharmacist if you notice any of the following and they worry you:
- Diarrhoea
- Tummy pain
- Constipation
- Nausea (feeling sick)
- Vomiting
- Reduced appetite
- Weight loss
- A sore inside the mouth
- Looking pale
- Feeling tired
- Having little or no energy
- Shortness of breath when exercising
- Feeling dizzy
- Headache
- Low blood pressure
- Bleeding
If you have any questions or concerns about side effects, speak to your doctor, nurse or pharmacist. You can get further information about side effects, by reading the VENCLEXTA Consumer Medicine Information.
When taking VENCLEXTA in combination with either ibrutinib, obinutuzumab, rituximab, azacitidine or low dose cytarabine, there may be additional possible side effects associated with these medicines. Speak to your healthcare team about other possible side effects that may occur because of your combination therapy.
For further information about side effects, read the Consumer Medicine Information.
TAKING YOUR MEDICINE SAFELY
Take VENCLEXTA exactly as your doctor has prescribed. If you have questions about how to take VENCLEXTA, ask your doctor or pharmacist.
How to take VENCLEXTA
- Take the tablets during or immediately after a meal, at about the same time every day.
- Swallow the tablets whole with a full glass of water.
- DO NOT chew, crush or break the tablets.
Staying hydrated
It is important to stay hydrated when taking VENCLEXTA and drink about 6 to 8 glasses (1.5 to 2 litres) of water each day as instructed.
Make especially sure you drink your 6-8 glasses of water on these days:
- The two days before, and the day that you take your first VENCLEXTA dose.
- The two days before, and the day you increase your VENCLEXTA dose.
Things you should do when taking VENCLEXTA
- Check with your doctor
If you:- have any problems with your liver or kidneys
- think you may have an infection
- have had any recent immunisations
- Take VENCLEXTA with a meal and water around the same time of day every day.
Tablets should be swallowed with a full glass of water without chewing, crushing, or breaking. - Stay hydrated
Drink plenty of water (six to eight glasses or 1.5 to 2 litres per day) as instructed when taking VENCLEXTA. - Blood tests
It is important to follow your doctor or nurse’s instructions very carefully regarding when to have your blood tests. - Other medications
Tell your doctor or pharmacist if you are taking any other medications, including prescription and over-the-counter medicines, vitamins or other supplements. - Follow the instructions
Take VENCLEXTA exactly as your healthcare provider tells you to take it. - When visiting healthcare professionals
Remind any doctor or dentist you visit that you are using VENCLEXTA.
Things you should not do when taking VENCLEXTA
- Do not start taking VENCLEXTA
until you have reviewed the instructions with your doctor. - Don’t crush, chew, or break the tablets.
Be sure to swallow them whole. - Don’t:
- drink grapefruit juice
- eat grapefruit
- eat Seville oranges
(often used in marmalades) - eat Starfruit
- For patients with CLL or SLL, don’t take VENCLEXTA if you are taking any of the following medicines:
- Ketoconazole
- Voriconazole
- Itraconazole or posaconazole, which are used to treat fungal infections
- Clarithromycin, which is used to treat bacterial infections.
- Ritonavir, which is used to treat HIV or Hepatitis C virus.
- Don’t take an additional dose if you vomit after taking VENCLEXTA.
Take the correct dose at the usual time the next day. - Don’t stop using VENCLEXTA or change your dose
Unless your doctor tells you to. - Don't take VENCLEXTA if you are pregnant or are breastfeeding.
- If you are a woman of child-bearing age, you must use a highly effective form of contraception during treatment with VENCLEXTA and for at least 30 days after your last dose.
- Don't take VENCLEXTA if you are allergic to ventoclax, or any of the ingredients listed in the CMI.
Tell your doctor, nurse or pharmacist if you notice anything else that may be making you feel unwell.
If you have any questions or concerns about side effects, speak to your doctor, nurse or pharmacist. If you are being treated with VENCLEXTA you can get further information about potential side effects by reading the Consumer Medicine Information available at medsafe.govt.nz.
WHAT TO DO IF YOU MISS A DOSE OF VENCLEXTA
It is important not to miss a dose of this medicine.
If you vomit after taking VENCLEXTA, do not take an extra dose. Take the correct dose at your usual time the next day. If you are unsure, talk to your doctor, nurse or pharmacist.
WHAT TO DO IF YOU TAKE TOO MUCH VENCLEXTA
If you think you (or anyone else) may have taken too much VENCLEXTA, immediately telephone your doctor or the National Poisons Centre on 0800 764 766, or go to the Emergency Department at your nearest hospital.
Do this even if there are no signs of discomfort or poisoning.
Download the Consumer Medicine Information
Read the Consumer Medicine
Information for VENCLEXTA here.
NZ-VEN-xxxxxx. TAPS BGxxxx. ONO0212. September 2026.
For more information about AbbVie, the maker of VENCLEXTA, visit www.abbvie.co.nz
For medical information enquiries regarding VENCLEXTA please contact medinfoanz@abbvie.com
The content on this site is intended solely for New Zealand residents. The information is intended for informational purposes only and should not be used to replace a discussion with a healthcare professional. All decisions made regarding patient care must be handled by a healthcare professional and be made based on the unique needs of each patient. This website has been developed and is funded by AbbVie Limited, Wellington. The person shown is from stock photography (model) and is not an actual patient.
VENCLEXTA in combination with obinutuzumab or ibrutinib is fully funded for untreated chronic lymphocytic leukaemia (CLL). VENCLEXTA in combination with rituximab is fully funded for relapsed/refractory CLL. VENCLEXTA in combination with azacitidine or low dose cytarabine is fully funded for acute myeloid leukaemia (AML). Special Authority criteria apply. Refer to the VENCLEXTA PHARMAC Special Authority criteria.
IMPORTANT INFORMATION ABOUT VENCLEXTA®
VENCLEXTA® is a prescription medicine containing venetoclax. Venclexta is available as film-coated tablets of various strength (10 mg, 50 mg, 100 mg venetoclax). It is used to treat adults with chronic lymphocytic leukaemia (CLL) or small lymphocytic lymphoma (SLL) or acute myeloid leukemia (AML). Venclexta is taken alone or in combination with other medicines. Your doctor will let you know which combination medicines, how to take them, and how long to take them. Typically, you will start treatment with Venclexta at a low dose. If you are taking Venclexta for CLL or SLL, your doctor will gradually increase your dose over 5 weeks up to the full dose. If you are taking Venclexta for AML, your doctor will gradually increase your dose up to the full dose over 3, or 4 days, depending on the combination medicine used. Use strictly as directed by your doctor. Venclexta has risks and benefits. You must not take it if you are allergic to venetoclax or to any of the inactive ingredients. For CLL or SLL, do not take Venclexta if you are taking any of the following medicines: medicines used to treat or prevent fungal infections, including ketoconazole, posaconazole, voriconazole, itraconazole; clarithromycin (an antibiotic); or ritonavir (a medicine used to treat HIV and hepatitis C). Do not drink grapefruit juice, or eat grapefruit, starfruit or Seville oranges or marmalades. Do not give Venclexta to children and adolescents under 18 years of age. Do not take Venclexta if you are pregnant or plan to become pregnant, or if you are breastfeeding or plan to breastfeed. If you are a woman of child-bearing age, you must use a highly effective form of contraception during treatment with Venclexta and for at least 30 days after your last dose. Tell your doctor, nurse, or pharmacist if you have any kidney or liver problems; if you think you may have an infection; or if you recently received or are scheduled for any vaccinations. Do not stop using Venclexta or change the dose without checking with your doctor. Venclexta can cause tumour lysis syndrome (TLS), which is caused by the fast breakdown of cancer cells. TLS is a very serious side effect that can be fatal. TLS is most likely to occur when you are first starting treatment. To help prevent TLS, it is important to stay hydrated and drink water every day when taking Venclexta. Particularly, starting two days before and on the day of your first dose of Venclexta and every time the dose is increased, drink 6 to 8 glasses (approximately 1.5-2 L total) of water each day. Let your healthcare provider know immediately if you experience: fever or chills; feeling sick or vomiting; being short of breath; feeling unusually tired; changes in your heart rate (slow, fast or irregular); your urine looks dark or cloudy; feeling confused; convulsions or fits; or pain in the muscles or joints while on treatment with Venclexta. Ensure you follow all your doctor’s instructions carefully and keep all your appointments, including those for blood tests. You may experience a low number of neutrophils, a type of white blood cells – this can be severe and need treatment. Your doctor will check your blood counts during treatment with Venclexta. You may experience infections during treatment with Venclexta. Some infections can be very serious or even fatal. Your doctor will closely monitor and treat you right away if you have fever or any signs of infection during treatment with Venclexta. Tell your doctor immediately if you have signs of an infection before, or while taking Venclexta, including: fever or chills, feeling weak or confused, cough, runny nose, sore throat; congestion on the chest; or pain or burning when passing urine. Some of the less serious side effects of Venclexta include diarrhoea; tummy pain; constipation, nausea (feeling sick); vomiting; reduced appetite; weight loss; mouth sores; looking pale; feeling tired; having little or no energy; shortness of breath when exercising; feeling dizzy; headache; low blood pressure; bleeding. Tell your doctor or pharmacist if you notice anything else that is making you feel unwell. Some medicines and Venclexta may interfere with each other, so tell your doctor if you are taking medicines containing any of the following: ketoconazole, posaconazole, voriconazole, itraconazole, fluconazole, clarithromycin, ciprofloxacin, erythromycin, ritonavir, diltiazem, verapamil, captopril, felodipine, dronedarone, amiodarone, quinidine, rifampicin, carvedilol, ciclosporin, quercetin, ranolazine, ticagrelor, azithromycin, nafcillin, carbamazepine, phenytoin, St John’s wort (Hypericum perforatum), bosentan, efavirenz, etravirine, modafinil, warfarin, digoxin, everolimus, or sirolimus. Tell your doctor or pharmacist if you are taking any other medicines, including any medicines, vitamins or supplements that you buy without prescription. Tell any other doctors, pharmacists, dentists, or surgeons treating you that you are taking Venclexta and remind them before you start any new medicines. If you have any questions about using Venclexta, including its risks and benefits, how much to use, how and when to use it, or storage conditions, ask your healthcare professional and refer to the Consumer Medicine Information (CMI) available from www.medsafe.govt.nz or free phone 0800 900 030. Ask your doctor if Venclexta is right for you. Use strictly as directed. If symptoms continue, or you have side effects, see your doctor, pharmacist, or healthcare professional. V7a.
©2026 AbbVie. All rights reserved. AbbVie® is a registered trademark of AbbVie Inc. VENCLEXTA® and its designs are registered trademark of AbbVie Manufacturing Management Unlimited Company. AbbVie Limited, Wellington 6011, New Zealand TAPS BGxxxx. NZ-VEN-200006. ONO0212. September 2026.