Spah.scot.nhs.uk

Scottish Paediatric & Adult
Haemoglobinopathy
Managed Clinical Network
Information about
Hydroxycarbamide
(Hydroxyurea) in
Sickle Cell Disease
What is hydroxycarbamide?
Hydroxycarbamide is a drug which we use to treat a variety of blood and bone marrow diseases, including sickle cell disease. Hydroxycarbamide comes either as a capsule or a tablet which you swallow. You usually take it once a day. How does hydroxycarbamide help patients with
sickle cell disease?
• Fewer painful and less severe crises and hospital • Fewer episodes of acute chest syndrome• Fewer blood transfusions• An improvement in your quality of life.
Hydroxycarbamide works for most patients but not all. We cannot predict who it will work for.
Which sickle cell patients should consider
hydroxycarbamide?
We will consider giving you Hydroxycarbamide if: • You have moderately severe or severe sickle cell disease• You have had several episodes of acute pain (usually three or more admissions to hospital or crises at home in a 12 • You have had an episode of acute sickle chest syndrome • You are unsuitable for or unable to tolerate a long term exchange blood transfusion programme.
How does hydroxycarbamide work in sickle cell
disease?
Red blood cells contain haemoglobin which transports oxygen around the body. Red blood cells containing sickle haemoglobin (HbS) can deform into a stiff sickle shape in the blood stream and multiple sickled red cells can stick together. These changes can lead to a blockage of blood vessels and interruption of blood flow and oxygen to the parts of the body they supply. The end result is symptoms of sickle cell disease including pain and shortness of breath.
Hydroxycarbamide increases the amount of fetal (baby) haemoglobin (HbF) in the blood. Red cells containing HbF cannot sickle and stick together.
Hydroxycarbamide also works by decreasing the number of white blood cells and platelets, which are often high in patients with sickle cell disease. • White blood cells help to fight infection but also contain chemicals which cause inflammation and can trigger sickle crises. With decreased numbers of white • Platelets help the blood to clot and increased numbers may make blood too sticky. Reducing the platelet count with hydroxycarbamide can reduce this It may take up to 3 months for you to experience the full benefit of hydroxycarbamide treatment as described in “How does hydroxycarbamide help patients with sickle cell disease?” How much hydroxycarbamide do I take?
Your haematologist will decide your starting dose according to your weight. Depending on how you tolerate it, your haematologist may increase the dose until you get the maximum benefit. Each capsule or tablet contains 500mg and you can take it on an empty stomach or with food.
Try to take hydroxycarbamide at the same time each day. If you forget to take a dose, take the missed dose as soon as you remember. However, if it is almost time for your next dose, skip the missed dose and then continue as usual.
Do not take a double dose to make up for a missed dose
and do not take more than one dose in one day.
What are the side effects of hydroxycarbamide?
Most people have few side effects with hydroxycarbamide. The potential side effects include nausea, vomiting, rashes, diarrhoea, weight gain, upset liver function, darkening of skin, nails and mouth or leg ulcers. • red cell count which may lead to an increase in • white cell count which may lead to infection • platelet count which may lead to bruising or bleeding.
If you notice an increase in tiredness, signs of infection, high temperatures, bruising or bleeding you should stop taking your hydroxycarbamide and contact your haematologist as soon as possible. You will need to attend hospital for an assessment and blood tests if these symptoms occur.
In the past there were concerns that hydroxycarbamide might increase the risk of leukaemia. However a large study over several years did not show an increase in leukaemia in sickle cell patients who take hydroxycarbamide.
How will you monitor hydroxycarbamide?
Because hydroxycarbamide can affect your red cell, white cell,
platelet count and liver tests, we monitor these blood tests.
When you first start your treatment, you will have blood tests
every 2 weeks and any time there has been a dose change.
We also monitor your HbF levels. Once you are on a stable
dose, we monitor your blood every four to twelve weeks. We
will not give you prescriptions unless you attend for these
blood tests.
Family planning and hydroxycarbamide
We recommend that all of our patients use contraception
whilst taking hydroxycarbamide and for three months after
stopping the drug.
Male patients: Hydroxycarbamide may reduce your sperm
count and cause production of abnormal sperm. This
usually returns to normal 3 months after you stop taking
hydroxycarbamide. We recommend you discuss freezing your
sperm before you start hydroxycarbamide.
Female patients: You should not become pregnant whilst
on hydroxycarbamide as it has the potential to cause harm
to the fetus.
Female patients on hydroxycarbamide should stop taking the drug at least 3 months before conception to reduce this risk. If you become pregnant whilst taking hydroxycarbamide, please stop taking the drug and contact your doctor immediately.
You should not breast feed whilst taking hydroxycarbamide as the drug may be expressed in breast milk. You can bottle feed your baby and restart your hydroxycarbamide or breast feed and remain off your hydroxycarbamide.
Local Contact Information
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Source: http://www.spah.scot.nhs.uk/Documents/Final%20Hydroxycarbamide%20leaflet.pdf