Polycythaemia vera (PV)
Polycythaemia vera (PV) is a slow-growing blood cancer where your body makes too many red blood cells. Find out about symptoms, tests, treatment and looking after yourself with PV.

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What is PV (polycythaemia vera)?
If you have PV, your body makes too many red blood cells. This makes your blood thicker than normal and raises your risk of developing blood clots (thrombosis). This can lead to problems like heart attack or stroke. Treatment for PV can lower this risk.
PV is classed as a type of blood cancer because it involves cells growing our of control, in this case, red blood cells. It’s one of a group of blood cancers known as myeloproliferative neoplasms (MPNs).
Over 1,000 people in the UK are diagnosed with PV every year. There are around 8,500 people currently living with PV in the UK.
Finding out you have PV
It's never easy to hear the word cancer, but we can support you in a way that suits you. Find out more about how we can help.
You may like to sign up to our weekly support email for people who have been recently diagnosed. This will bring you regular information and ideas to help you through those difficult first weeks.

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We'll send you clear and simple information, practical tips, and advice from other people with blood cancer, to help during the first few weeks and months after diagnosis.
Causes of PV
PV starts with a genetic change (a mutation), usually in a gene called JAK2. This mutation happens during someone's lifetime. It's very rare for it to be passed down in families.
PV is more common in people over 50, and slightly more common in men than women.
Prognosis for PV
PV can't be cured but it can be treated effectively. Treatment can lower your risk of blood clots and help to control any symptoms you may have so you can get on with your life.
PV can develop into another type of blood cancer, but the chance of this happening is low.
Everyone is different, so speak to your hospital team about your personal prognosis.
Symptoms of PV
People report a range of common symptoms, including:
- headaches
- confusion
- dizziness
- blurred vision
- night sweats
- itching (pruritis)
- extreme tiredness (fatigue)
- unusual bleeding such as nosebleeds, bruising easily or heavy periods
- red-looking eyes
- red-looking skin (this may be harder to see on darker skin tones)
- a swollen spleen, causing a feeling of fullness or pain after eating small amounts
- gout, causing pain in your joints.
You won't have all these symptoms and you may not have any at all. It's important to be aware of the symptoms of blood clots, as this is the main risk to your health from PV.
Tests for PV
You will need tests to decide if you have PV. If your doctor confirms that PV is the right diagnosis you will also have tests to monitor the PV and help your doctor decide on the best treatment.
Most tests will be blood tests. Some people may have a scan or a bone marrow biopsy, but these tests aren't routinely needed.
Treatment for PV
Treatment aims to keep the number of red blood cells in your blood at a low level to lower your risk of blood clots. The treatment you have will depend on your age, your test results, and any other health conditions you have.
Daily aspirin, venesection (blood-letting) and cytoreductive drugs (drugs that reduce your number of red blood cells) are different treatment options depending on your personal circumstances.
Treatment side effects
Drugs used to treat PV may cause some side effects. This is very individual - you won't necessarily react the same way as someone else on the same drug.
If you notice a change in how you feel, tell your hospital team who can help you manage any side effects from your medication.
Some drugs may affect your fertility, so speak to your team about your treatment plan if you may want to have children in the future.

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Includes understanding PV, treatments and how to look after yourself
Looking after yourself with PV
Lifestyle doesn't cause PV, but there are things you can which might help you feel better, mentally and physically. Staying active, drinking plenty of fluids and stopping smoking are just a few ideas.
It's also important to look after your mental health. We have more information to help you find what works for you.
If someone you love has been diagnosed with PV
If your family member or friend has been diagnosed with PV, you might find our information for family and friends helpful. It covers how to support someone with blood cancer, practical tips, coping with your own emotions, and real stories from other friends and family members.
Research and clinical trials
Many people find hope in the knowledge that scientists are researching better and kinder treatments for PV and other MPNs. Find out more about our MPN research: visit our research project page and select "myeloproliferative neoplasms (MPN)" in the conditions filter.
Thank you to Consultant Haematologists Clare Kane and Mallika Sekhar for checking the medical content of our PV information, and to Clinical Nurse Specialists Jodie Nightingill and Madeleine Ward for their guidance and support.