Chelation therapy for iron overload in sickle cell and thalassaemia

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1 Networked Services Chelation therapy for iron overload in sickle cell and thalassaemia Information for adult patients at King s College Hospital only This leaflet answers some of the questions you may have about the drugs we use to treat iron overload. It explains how they work and the benefits and risks. It contains important information so please read it carefully. If you have any questions or concerns, please do not hesitate to speak to your haematology doctor. 1

2 What is iron overload? When you have regular blood transfusions to treat sickle cell or thalassaemia conditions, large amounts of iron build up in your body (iron overload). People with certain types of thalassaemia can have a build up of iron without having repeated transfusions. Excess iron can damage organs such as the heart, liver, pancreas and the hormone glands. Treatment for iron overload is called iron chelation. We assess you when you have had more than 20 units of red blood cells and treatment starts when needed. What are the symptoms? Symptoms of iron overload depend on where the extra iron is located in your body. Sometimes you only have symptoms when iron overload is severe. Too much iron can damage: The heart: It can cause heart failure and irregular heart rhythms. Symptoms include feeling very tired, breathless and not being able to do as much physical activity. The liver: It can cause scarring of the liver (cirrhosis). Symptoms include loss of appetite, nausea, tiredness, jaundice (yellowing of the skin and whites of eyes) and itchy skin. The pancreas: It can lead to diabetes. Diabetes is irreversible and treated with insulin. Symptoms include feeling very thirsty, very tired, urinating more often (especially at night) and weight loss. Hormone glands: The thyroid may slow down which means it does not produce enough chemicals (hormones). Symptoms of an underactive thyroid include tiredness, weight gain, depression, dry skin and hair. 2

3 Sex hormone glands: You may not produce enough sex hormones (men: testes, women: ovaries). This can cause fertility problems and difficulties with the development of secondary sexual characteristics (features you develop during puberty). For example, the development of breasts for females, and for males, the deepening of voice, and the growth of facial hair and body hair). Women: it can cause weak bones (osteoporosis) and your menstrual periods may be delayed, irregular or stop. Men: it can affect your testosterone levels. This can cause sexual dysfunction, increased body fat and reduced muscle mass. It is important to treat iron overload as early as possible to reduce and prevent damage. How do you measure iron overload? There are different types of tests to measure iron levels in your blood. These include: Scans: MRI scans of your liver and heart are very useful to assess whether you have a build-up of iron. A special type of MRI scan will show how your heart is functioning. Blood tests: One of the first tests that we do, measures your ferritin level. Ferritin is a protein that shows how much iron is stored in the body. If the amount of ferritin in your body continues to rise, it could mean that you have a build-up of iron. We will give you medication to lower your ferritin level. 3

4 A range of other tests find out how your organs are functioning and if you have a build-up of iron. These tests may be for thyroid function, liver function, sex hormone level, some vitamin and mineral levels, screening tests for diabetes and adrenal gland problems. We will give you more information about any other tests you have. What are the benefits? Extra iron is removed from your body to prevent damage to your organs and glands. What are the risks? There are different risks and side effects depending on the type of medication you take. Please read this leaflet for the risks of each medication. If you do not have treatment, iron will continue to build up in your organs and glands, and cause damage. Are there any alternatives? There are no alternatives to iron chelation. How is iron overload treated? We use medicine (the iron chelator) to remove the extra iron. If you already have iron overload, it will take longer for the iron to leave your body. It is very important to take your medication regularly so you have no extra iron in your body. 4

5 What are the different medications available for chelation therapy? We use three types of medication: Deferisarox (Exjade) Desferrioxamine (Desferal) Deferiprone (Ferriprox). Your doctor will decide which type of chelation treatment is best for you. This depends on where the extra iron is and the organ it is affecting. Is important that you take your medication as prescribed, and check the expiry date. Deferasirox (Exjade) Desferasirox is especially effective for removing iron from the liver. Important- do not use deferasirox if: You think you may be pregnant; tell your doctor as soon as possible You are breastfeeding. How do I take it? By mouth as a dispersible (quick to dissolve) tablet. Do not chew or swallow them whole. You should put the tablet in water, orange juice or apple juice. You should take it on an empty stomach at least 30 minutes before you eat, at the same time each day, to lower side effects. How often should I take desferasirox? Once a day. If you occasionally miss a dose, it will not cause any problems, but if you often miss doses, you could develop other 5

6 medical problems. If you miss a dose, don t take it when you remember - wait until your next dose is due. If you take too much, go to your local Emergency Department (A&E) immediately. What are the side effects? Very common It can affect the function of your kidneys. You will have regular blood tests so that we can closely monitor your kidneys. Common Nausea, sickness and diarrhoea; these usually improve over time. If you have diarrhoea often, tell your doctor so that they can give you anti-diarrhoea medication. Stomach pain and indigestion Rashes. This usually resolves on its own Changes in liver function tests. We will monitor this. Uncommon Black stools Tiredness Problems with vision Problems with hearing. If you vomit blood and/or have black stools, stop taking this medicine immediately and go to your local ED straight away. It can lower the number of different types of blood cells. If it lowers one of the types of white blood cells, it can reduce your body s ability to fight infection. You will have regular blood tests so that we can closely monitor your blood counts. 6

7 If you have any of the following symptoms, your white blood cell count may be low and you could have an infection. Please contact the Supportive Therapy Unit (in working hours) or your local ED (out of hours) immediately. a high temperature (above 38 C) chills and shivering sore throat mouth ulcers. If you notice bruising, bleeding, unusual tiredness or weakness, it could mean you have a low blood count. Go to your local ED immediately. It is important that you have regular hearing and eye monitoring checks every year, and go to all of your appointments Desferrioxamine (Desferal) Do not use deferrioxamine if: You are allergic to any of the ingredients in deferrioxamine You think you may be pregnant; tell your doctor as soon as possible. How do I take it? This is given as an injection under the skin (subcutaneously) using a special pump. Your doctor may decide that you should have this medicine over a period of time, through a vein. 7

8 How often should I take desferrioxamine? You need to use the pump continuously for at least 8-10 hours, three-seven times a week. However, your doctor will decide your dose and how often you need to take it. For treatment to be effective, you must make sure that the pump is properly connected and turned on as discussed with your nurse. If you occasionally miss a dose, it will not cause any problems, but if you often miss doses, you could develop other medical problems. If you miss a dose, don t take it when you remember - wait until your next dose is due. If you take too much, go to your local Emergency Department (A&E) immediately. What are the side effects? Some people have no side effects. However, some possible side effects include: Very Common Skin irritation or blisters where the needle was put in Aching muscles or joints. Common Nausea Uncommon Sickness Ringing in your ears (tinnitus). Rare Problems with your vision Some bacteria grow on the extra iron that is removed. Yersinia bacteria can cause abdominal pain, fever, diarrhoea and vomiting. If you get any of these symptoms, stop your treatment immediately and contact the Supportive Therapy Unit (in working hours) or go to your local ED if out of hours. 8

9 It is important that you have regular hearing and eye monitoring checks every year, and go to all of your appointments. How do I store desferrioxamine? Keep in the fridge in the original packaging Do not freeze Keep out of reach of children. Deferiprone (Ferriprox) Deferiprone is particularly effective for removing iron from the heart. Important- do not use deferiprone if: You are allergic to any of the ingredients in deferiprone You are breastfeeding You plan to become pregnant or think you may be pregnant, as it can affect your unborn baby You are having sexual intercourse without contraception. We advise women who have periods to use contraception. How do I take it? By mouth (orally) as a tablet or liquid solution. How often should I take deferiprone? Three times a day. It is important to only take the dose prescribed. Take it with some water or other liquid. If you occasionally miss a dose, it will not cause any problems, but if you often miss doses, you could develop other medical problems. If you miss a dose, don t take it when you remember - wait until your next dose is due. If you take too much, go to your local Emergency Department (A&E) immediately. 9

10 What are the side effects? It can lower one of the types of white blood cells, which reduces your body s ability to fight infection. You will have regular blood tests so that we can closely monitor your levels. If you have any of the following symptoms, your white blood cell count may be low and you could have an infection. Please contact the Supportive Therapy Unit (in working hours) or go to your local ED (out of hours) immediately. a high temperature (above 38 C) sore throat mouth ulcers. Very Common Red/brown urine. This is normal as the excess iron (a red/brown colour) comes out in your urine. Nausea and sickness - you can often reduce this by taking your tablets with your meals Stomach pain. Common Joint pain Increased appetite Low white blood cell count. The information in this leaflet is to be used as a guide only. Please discuss the specific details of your treatment with your doctor and remember to ask if there is anything that you are not sure of. 10

11 Who can I contact with queries and concerns? If you have questions about your treatment, please contact: Chengetai Muzah, Clinical Nurse Specialist Tel: or Dr Moji Awogbade, Consultant haematologist Tel: Supportive Therapy Unit Tel: / 2963 Where can I get more information? Sickle Cell Society UK Thalassaemia Society Sharing your information We have teamed up with Guy s and St Thomas Hospitals in a partnership known as King s Health Partners Academic Health Sciences Centre. We are working together to give our patients the best possible care, so you might find we invite you for appointments at Guy s or St Thomas. To make sure everyone you meet always has the most up-to-date information about your health, we may share information about you between the hospitals. Care provided by students We provide clinical training where our students get practical experience by treating patients. Please tell your doctor or nurse if you do not want students to be involved in your care. Your treatment will not be affected by your decision. 11

12 PALS The Patient Advice and Liaison Service (PALS) is a service that offers support, information and assistance to patients, relatives and visitors. They can also provide help and advice if you have a concern or complaint that staff have not been able to resolve for you. The PALS office is located on the ground floor of the Hambleden Wing, near the main entrance on Bessemer Road - staff will be happy to direct you. Tel: Fax: kch-tr.pals@nhs.net You can also contact us by using our online form at If you would like the information in this leaflet in a different language or format, please contact PALS on Corporate Comms: 1088 PL695.2 September 2015 Review date August 2018