Hydroxycarbamide (Hydrea)

Hydroxycarbamide is a chemotherapy treatment. It is also known as Hydrea. It was once also called Hydroxyurea.  

It is a treatment for:

• chronic myeloid leukaemia (CML)
• polycythaemia vera (PCV)
• essential thrombocythemia (ET)
• acute myeloid leukaemia (AML)
• cervical cancer (cancer of the neck of the womb)

For cervical cancer, you usually have it in combination with radiotherapy. 

How it works

Hydroxycarbamide is one of a group of chemotherapy drugs known as anti metabolites. These drugs stop cells making and repairing DNA. Cancer cells need to make and repair DNA in order to grow and multiply.

How you have it

Hydroxycarbamide comes as capsules that you swallow whole, with a glass of water. You can empty the contents of the capsules into a glass of water if you have difficulty swallowing capsules. Then drink it all straight away. Don't leave any behind in the glass.

You can take hydroxycarbamide with or without food. 

Taking your capsules

You should take the right dose, not more or less.

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

If you take more hydroxycarbamide than you should

Contact your doctor or nurse straight away. 

If you forget to take hydroxycarbamide

Do not take the missed dose and take your next dose at the usual time. Do not take a double dose to make up for the forgotten dose.

When you have it

You usually have hydroxycarbamide as a course of several cycles of treatment. Sometimes there might be a break between cycles.

You can have hydroxycarbamide in combination with radiotherapy. When this happens, you usually start taking hydroxycarbamide 7 days before the radiotherapy 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.

Side effects

How often and how severe the side effects are 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. 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:

Risk of bruising and bleeding

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).

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, headaches, feeling cold and shivery and generally 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. 

Breathless and looking pale

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

Loss of appetite

You might lose your appetite for various reasons whilst having cancer treatment. Sickness, taste changes or tiredness can put you off food and drinks.

Inflammation of the lining of the gut and bowel

This can cause bleeding from your back passage when pooing and blood in your poo. It can also be very painful. Contact your advice line or tell your doctor or nurse if you have any of these symptoms.

Tummy (abdominal) discomfort or pain

Tell your treatment team if you have this. They can check the cause and give you medicine to help. 

Hair loss

You could lose all your hair. This includes your eyelashes, eyebrows, underarms, legs and sometimes pubic hair. Your hair will usually grow back once treatment has finished but it is likely to be softer. It may grow back a different colour or be curlier than before. 

Skin and nail changes

Skin and nail problems include a skin rash, dry skin, itching and darker skin. Your nails may also become brittle, dry, change colour or develop ridges. This usually goes back to normal when you finish treatment.

Sore weak muscles 

Your muscles might feel sore, weak and tired especially when climbing stairs, walking or getting out of a chair. 

Problems passing urine

You might find it painful and difficult to pass urine. Contact your advice line or tell your doctor or nurse if this happens.

An increased level of certain substances in the blood

You might have an increased level of creatinine, urea and uric acid in the blood. You have regular blood tests to check these. 

High temperature

If you get a high temperature, let your healthcare team know straight away. Ask them if you can take paracetamol to help lower your temperature.

Chills

You might feel cold for no apparent reason. Chills can also happen when you have a high temperature

Having no energy or strength

This is usually mild. You can do things to help yourself, including some gentle exercise. It’s important not to push yourself too hard and eat a well balanced diet.

Talk to your doctor or nurse if this effect is stopping you from doing your usual daily activities.

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:

• skin ulcers especially on your legs
• skin cancer
• feeling disorientated and having hallucinations
• fits (convulsions), dizziness, headaches and feeling drowsy
• damage to the nerves in your hands and feet causing pain, tingling or numbness
• changes to your lungs included fluid on the lung and inflammation causing shortness of breath
• changes or damage to your liver
• diarrhoea or constipation

Rare side effects

This side effects happens in fewer than 1 in 100 people (fewer than 1%). You might have one or more of them. They include:

• inflammation of the pancreas
• feeling or being sick
• sore mouth

Coping with side effects

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

What else do I need to know?

Other medicines, food and drink

Cancer drugs can interact with some other medicines and herbal products. Tell your doctor or pharmacist about any medicines you are taking. This includes vitamins, herbal supplements and over the counter remedies.

Lactose intolerance

This drug contains lactose (milk sugar). If you have an intolerance to lactose, contact your doctor before taking this medicine.

Alcohol

Check with your doctor to see if drinking alcohol may harm you while having this treatment. 

Loss of fertility

You may not be able to become pregnant or father a child after treatment with this drug. Talk to your doctor before starting treatment if you think you may want to have a baby in the future.

Men might be able to store sperm before starting treatment. And women might be able to store eggs or ovarian tissue. But these services are not available in every hospital, so you would need to ask your doctor about this.    

Contraception and pregnancy

This drug may harm a baby developing in the womb. It is important not to become pregnant or father a child while you are having treatment with this drug and for at least 3 months afterwards.

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

Breastfeeding

Don’t breastfeed during this treatment because the drug may come through into your breast milk.

Treatment for other conditions

Always tell other doctors, nurses, pharmacists or dentists that you’re having this treatment. For example, if you need treatment for anything else, including teeth problems.

Immunisation

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 about this treatment

For further information about this treatment go to the electronic Medicines Compendium (eMC) website.

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

This page is due for review. We will update this as soon as possible.