Venetoclax and low dose cytarabine

Venetoclax and cytarabine are cancer drugs. You can see below how to pronounce the drug names:

• venetoclax (ven-eet-oh-clax)
• cytarabine (sye-ta-ra-bin)

You have these drugs as a treatment for acute myeloid leukaemia (AML). 

How do venetoclax and low dose cytarabine work?

Venetoclax is a type of targeted cancer drug called a cancer growth blocker. These block proteins on cancer cells that help them grow and survive. Venetoclax blocks a protein called BCL2. So you might hear it called a BCL2 inhibitor. By blocking this protein it is able to kill and slow down the growth of cancer cells.

Cytarabine is a type of chemotherapy called an anti metabolite . It stops cells making and repairing DNA . Cancer cells need to make and repair DNA so they can grow and multiply.

How do you have venetoclax and low dose cytarabine?

You take venetoclax as tablets once a day with a meal. You take them at the same time each day, usually with breakfast. You swallow the tablets whole with a glass of water. 

You have cytarabine as an injection under the skin (subcutaneously).

Taking your tablets

Speak to your pharmacist if you have problems swallowing the tablets.

Whether you have a full or an empty stomach can affect how much of a drug gets into your bloodstream.

You should take the right dose, no more or less.

Talk to your healthcare team before you stop taking a cancer drug or if you miss a dose.

Injection under your skin (subcutaneous injection)

You usually have injections under the skin (subcutaneous injection) into the stomach, thigh or top of your arm.

You might have stinging or a dull ache for a short time after this type of injection but they don't usually hurt much. The skin in the area may go red and itchy for a while.

How often do you have venetoclax and low dose cytarabine?

You usually have venetoclax and low dose cytarabine as a course of several cycles of treatment . Each cycle of treatment lasts 28 days (4 weeks). Some people have to stay in hospital overnight (inpatient) for the few days of treatment. 

The amount (dose) of venetoclax you have starts off low and is gradually increased over the first few days of treatment. You might be asked to drink plenty of water before you start treatment and for the first few days. Or you might have fluids as a drip into a vein (intravenous).

Exactly how you have your drugs may depend on your circumstances. The following is an example:

You then start the next cycle of treatment.

Tests

You have blood tests before and during your treatment. They check your levels of blood cells and other substances in the blood. They also check how well your liver and kidneys are working.

Before treatment starts you may have a blood test to check for viruses such as hepatitis B, hepatitis C, and HIV . This is called a viral screen.

It’s important for your doctor to know if you have had any of these viruses. This is because this treatment can weaken your immune system and can cause the virus to become active again (reactivation). 

What are the side effects of venetoclax and low dose cytarabine?

Side effects can vary from person to person. They also depend on what other treatments you're having. 

When to contact your team

Your doctor, nurse or pharmacist will go through the possible side effects. They will monitor you during treatment and check how you are at your appointments. Contact your advice line as soon as possible if:

• you have severe side effects 

• your side effects aren’t getting any better

• your side effects are getting worse

Early treatment can help manage side effects better. 

We haven't listed all the side effects here. Talk to your healthcare team if you have any new symptoms that you think might be a side effect of your treatment.

Remember it is very unlikely that you will have all of these side effects. But you might have some of them at the same time.

Common side effects

These side effects happen in more than 10 in 100 people (more than 10%). You might have one or more of them. They include:

Increased risk of infection

Increased risk of getting an infection is due to a drop in white blood cells. Symptoms include a change in temperature, aching muscles, cough, headaches, feeling cold and shivery, pain or burning feeling when weeing, or generally feeling unwell. You might have other symptoms depending on where the infection is.

Infections can sometimes be life threatening. You should contact your advice line urgently if you think you have an infection. 

A serious reaction to an infection (sepsis)

Sepsis happens when your body has an overwhelming response to an infection. Symptoms can include feeling very unwell, not passing urine, slurred speech or confusion, breathlessness, mottled or discoloured skin, extreme shivering or muscle pain.

Lung problems

You might develop a cough or breathing problems. This could be due to infection, such as pneumonia or inflammation of the lungs (pneumonitis). 

Breathlessness and looking pale

You might be breathless and look pale due to a drop in red blood cells. This is called anaemia.

Bruising, bleeding gums or nosebleeds

This is due to a drop in the number of platelets in your blood. These blood cells help the blood to clot when we cut ourselves. You may have nosebleeds or bleeding gums after brushing your teeth. Or you may have lots of tiny red spots or bruises on your arms or legs (known as petechiae).

If your platelet count is very low, you might be at risk of bleeding from other parts of your body. 

Low levels of potassium in your blood

You might have low levels of potassium in the blood (hypokalaemia). Symptoms can include cramping in your arm or leg muscles, tingling or numbness, or feeling faint. You might feel like your heart is beating irregularly or strongly (palpitations).

Headaches 

Tell your healthcare team if you keep getting headaches. They can give you painkillers to help.

Dizziness

This drug might make you feel dizzy. Don’t drive or operate machinery if you have this.

Low blood pressure

Tell your doctor or nurse if you feel lightheaded or dizzy. You have your blood pressure checked regularly.

Decreased appetite and weight loss

You might not feel like eating and may lose weight. Eating several small meals and snacks throughout the day can be easier to manage. You can talk to a dietitian if you are concerned about your appetite or weight loss. 

Diarrhoea

Contact your advice line if you have diarrhoea. For example, in one day you have 2 or more loose bowel movements than usual. If you have a stoma , you might have more output than normal. Your doctor may give you anti diarrhoea medicine to take home with you after treatment.

Try to eat small meals and snacks regularly. It’s best to try to have a healthy balanced diet if you can. You don’t necessarily need to stop eating foods that contain fibre. But if your diet is normally very high in fibre, it might help to cut back on high fibre foods such as beans, nuts, seeds, dried fruit, bran and raw vegetables. 

Drink plenty to try and replace the fluid lost. Aim for 8 to 10 glasses per day.

Feeling or being sick

Feeling sick is usually well controlled with anti sickness medicines. Avoiding fatty or fried foods, eating small meals and snacks, drinking plenty of water, and relaxation techniques can all help.

It is important to take anti sickness medicines as directed by your doctor or pharmacist, even if you don’t feel sick. It is easier to prevent sickness rather than treating it once it has started.

Pain in different parts of the body

You might feel some pain in your tummy (abdomen) and joints. Speak to your doctor or nurse about what painkillers you can take to help with this.

Sore mouth

It may be painful to swallow drinks or food. Painkillers and mouth washes can help to reduce the soreness and keep your mouth healthy. 

Tiredness and weakness (fatigue)

You might feel very tired and as though you lack energy.

Various things can help you to reduce tiredness and cope with it, for example exercise. Some research has shown that taking gentle exercise can give you more energy. It is important to balance exercise with resting.

Liver changes

You might have liver changes that are usually mild and unlikely to cause symptoms. They usually go back to normal when treatment finishes. You have regular blood tests to check for any changes in the way your liver is working.

Occasional side effects

These side effects happen in between 1 and 10 out of every 100 people (between 1 and 10%). You might have one or more of them. They include: 

• high levels of uric acid in the blood – you have regular blood tests to check this, you may also have medicine to help get rid of this – drink plenty to help lower these levels
• inflammation of the gallbladder or gallstones - symptoms include sudden, severe tummy pain, fever, and yellowing of the skin and whites of your eyes

Other side effects

If you have side effects that aren't listed on this page, you can look at the individual drug pages:

• venetoclax
• cytarabine

Coping with side effects

We have more information about side effects and tips on how to cope with them.

What else do you need to know?

Other medicines, foods and drink

Cancer drugs can interact with medicines, herbal products, and some food and drinks. We are unable to list all the possible interactions that may happen. An example is grapefruit or grapefruit juice which can increase the side effects of certain drugs.

Tell your healthcare team about any medicines you are taking. This includes vitamins, herbal supplements and over the counter remedies. Also let them know about any other medical conditions or allergies you may have.

Loss of fertility

It is not known whether this treatment affects fertility in people. Talk to your doctor before starting treatment if you think you may want to have a baby in the future.

Pregnancy and contraception

This treatment may harm a baby developing in the womb. It is important not to become pregnant or get someone pregnant while you're having treatment and for at least 6 months afterwards.

Talk to your doctor or nurse about effective contraception before starting treatment. Let them know straight away if you or your partner become pregnant while having treatment. 

Breastfeeding

It is not known whether these drugs come through into the breast milk. Doctors usually advise that you don’t breastfeed during this treatment.

Treatment for other conditions

If you are having tests or treatment for anything else, always mention your cancer treatment. For example, if you are visiting your dentist.

Immunisations

Don’t have immunisations with live vaccines while you’re having treatment and for up to 12 months afterwards. The length of time depends on the treatment you are having. Ask your doctor or pharmacist how long you should avoid live vaccinations.

In the UK, live vaccines include rubella, mumps, measles, BCG, yellow fever and one of the shingles vaccines called Zostavax.

You can have:

• other vaccines, but they might not give you as much protection as usual
• the flu vaccine (as an injection)
• the coronavirus (COVID-19) vaccine - talk to your doctor or pharmacist about the best time to have it in relation to your cancer treatment

Members of your household who are aged 5 years or over are also able to have the COVID-19 vaccine. This is to help lower your risk of getting COVID-19 while having cancer treatment and until your immune system recovers from treatment.

Contact with others who have had immunisations - You can be in contact with other people who have had live vaccines as injections. Avoid close contact with people who have recently had live vaccines taken by mouth (oral vaccines) such as the oral typhoid vaccine. Sometimes people who have had the live shingles vaccine can get a shingles type rash. If this happens they should keep the area covered.

If your immune system is severely weakened, you should avoid contact with children who have had the flu vaccine as a nasal spray as this is a live vaccine. This is for 2 weeks following their vaccination.

Babies have the live rotavirus vaccine. The virus is in the baby’s poo for about 2 weeks and could make you ill if your immunity is low. Get someone else to change their nappies during this time if you can. If this isn't possible, wash your hands well after changing their nappy.

More information

For further information about each drug and the possible side effects go to the electronic Medicines Compendium (eMC) website. You can find patient information leaflets for each drug on this website.

You can report any side effect you have to the Medicines Health and Regulatory Authority (MHRA) as part of their Yellow Card Scheme.