Azathioprine for neurological (nervous system) conditions

Transcription

1 University Teaching Trust Azathioprine for neurological (nervous system) conditions Hope Building Neurology G W. Design Services, Salford Royal NHS Foundation Trust, All Rights Reserved Document for issue as handout. Unique Identifier: NOE 16 (16). Review date: April 2018.

2 Introduction Your doctor feels your condition may benefit from treatment with azathioprine. This leaflet aims to help you understand what to expect in terms of benefits, sideeffects and risks. Other important issues including how treatment is monitored will also be explained. If you have any questions please ask the doctor who has suggested this medication to you who will be happy to answer them. What is azathioprine and why am I being offered treatment? Azathioprine is an immunosuppressive drug. This means it can reduce the activity of the immune system which is your body s own defence system against infection. Azathioprine is used in the treatment of a wide variety of neurological (nervous system) conditions caused by disorders of the immune system. Some examples of these conditions are myasthenia gravis, inflammatory neuropathies (inflammation of nerves), inflammatory myopathies (inflammation of muscles), vasculitis (inflammation of blood vessels), multiple sclerosis and neuromyeltisoptica spectrum disorders (inflammation of brain and spinal cord). Your doctor will be able to explain the precise nature of your condition and the reason azathioprine may be of benefit. Azathioprine is not licensed for the treatment of your condition. Your doctor has recommended azathioprine because it is considered to be the best treatment for your condition or because you have not responded to or tolerated other drug treatments. Your doctor feels your condition may stabilise or improve on treatment but is likely to deteriorate without treatment. Your doctor also feels the potential benefit of treatment outweighs the side-effects and risks. If you are also taking steroids it may help to reduce the dose you need and therefore minimise any additional side-effects and risks linked with steroid treatment. What are the side-effects and risks? Azathioprine is usually well tolerated. However, it can sometimes cause flu-like symptoms such as fever or chills, fatigue and aches and pains in the muscles and joints. It can also sometimes cause mild hair loss, mouth ulcers, skin rashes and darkening of the skin or nails. Up to 30% of people (3 out of ten people) can get loss of appetite, nausea, vomiting and diarrhoea and if this is severe treatment may need to be stopped. Azathioprine can reduce the number of white blood cells, red blood cells and platelets in your blood stream due to its effects on the bone marrow. When white blood cells are low, infections are more likely to occur. You may get a fever and other signs of infection such as a sore throat, cough or pain on passing urine. When your red blood cells are low, you can become anaemic and this can cause you to look pale and feel weak. When your platelets are low you can bruise and bleed more easily. Azathioprine can affect your liver and this can cause you to become jaundiced (yellowing of the eyes and skin). It can very occasionally affect your pancreas (pancreatitis) and cause bad stomach pains. If you develop any of these problems you should contact your doctor or nurse straight away. Azathioprine may also increase the risk of developing certain types of cancer such as lymphoma, leukaemia and skin cancer. However, the evidence is by no means conclusive and the risk is likely to be small, with less than one person in 1000 developing cancer. The risk of cancer is usually greater in people receiving more powerful immunosuppressive drugs, or who have conditions that increase the risk of cancer. 1 G W. Design Services, Salford Royal NHS Foundation Trust, All Rights Reserved Document for issue as handout. Unique Identifier: NOE 16 (16). Review date: April

3 Conditions of the nervous system do not seem to increase the risk of cancer. It is important for you to have regular blood tests and take care to avoid too much sun, cover up and use sunscreen. Vaccinations If you require any form of vaccination once you have been started on azathioprine it is very important you discuss this with your GP or hospital doctor. You should not be routinely vaccinated using any of the live vaccines such as polio, rubella (German measles) and yellow fever. However, this may be necessary in certain circumstances. For example, rubella vaccination may be recommended to women of childbearing age because of risk to an unborn child. You should avoid contact with children who have been given live vaccinations for four to six weeks. It is safe and indeed recommended for you to receive the annual seasonal influenza ( flu ) and pneumococcal vaccinations. Tetanus vaccine is also safe. If you are exposed to chickenpox or shingles once you have been started on azathioprine and you have never had chickenpox it is important to seek medical advice because you may require antiviral treatment. Your doctor may consider treating you with an antibiotic called Septrin to reduce the risk of getting a particular type of infection called Pneumocystis pneumonia. This is a particular concern if you are also taking steroids. Pregnancy Azathioprine should not be given to women who are pregnant or likely to become pregnant without considering the risks and benefits because there have been reports of spontaneous abortion (miscarriage), premature birth and low birth weight babies following maternal exposure (treatment of mother when pregnant), particularly when steroids and Azathioprine are taken together. However, the evidence suggesting azathioprine increases the risk of these problems is very limited. Maternal exposure to azathioprine at any stage in pregnancy should not usually be regarded as medical grounds for termination of pregnancy (abortion) or any additional tests. You should consider having a pregnancy test before starting treatment and using contraception during treatment. Breast feeding It is usually recommended that women should not breast-feed whilst taking azathioprine because it is not known whether it is definitely safe to do so. However, only small amounts are found in breast milk and there is no evidence this is harmful. You should therefore consider whether the benefits of breast-feeding outweigh any potential risk. Fathering a child It is possible there may be a risk to the baby if the father has been treated with azathioprine within a few weeks of the baby being conceived (mother getting pregnant). However, the evidence is both limited and conflicting and it is therefore difficult to give meaningful advice as to whether treatment should be stopped before trying to father a child, especially if control of your condition is a priority. 3 4 G W. Design Services, Salford Royal NHS Foundation Trust, All Rights Reserved Document for issue as handout. Unique Identifier: NOE 16 (16). Review date: April 2018.

4 You may wish to consider using contraception during treatment and for six months after stopping azathioprine. Other medication and medical conditions The dose of azathioprine may need to be reduced or treatment avoided if you have a medical condition that affects your liver, kidneys or bone marrow. You should not take azathioprine if you have an allergy to a drug called mercaptopurine. Azathioprine may interact with other drugs including ACE inhibitors, allopurinol, anti-coagulants and certain antibiotics such as co-trimoxazole. It is important for your hospital doctor to see the medication you are taking before starting treatment to check it is safe to do so. It is also important that you tell your GP or hospital doctor you are on azathioprine before starting any other drugs in order to check it is safe to do so. Alcohol Azathioprine and alcohol may both damage your liver. You should try to keep your alcohol intake well within the maximum limits. The maximum for women is 2 to 3 units/day equivalent to 175ml glass of wine and the maximum for men is 3 to 4 units/day equivalent to a pint and a half of 4% beer. What happens if I agree to start treatment? Your doctor will need to see the other medications you are taking to check it is safe to start azathioprine. Your doctor will arrange a blood test to check your bone marrow, kidneys and liver are working properly. Your doctor may also check the level of an enzyme called thiopurinemethyltransferase (TPMT). This is because test results may influence the dose of azathioprine you are started on and the extent to which the dose is increased. Azathioprine will usually be prescribed by your hospital doctor but this responsibility may be transferred to your GP at some point. You may also be given a booklet to record your blood test results. This is a valuable document which should be kept safely and taken along with you whenever you visit your GP or hospital doctor. It is important blood test results are written in the booklet and kept up-to-date. Azathioprine is usually taken in tablet form once or twice a day with or after food to reduce nausea (feeling sick). Two different doses (25mg and 50mg tablets) are available for prescription. You should always check the dose is correct. The usual starting dose is 25 to 50 mg daily and depends upon your body weight. The dose may need to be reduced depending upon blood test results. The dose is then usually increased over a number of weeks or months until the best dose for you has been found (usually around 150mg daily). This depends upon your body weight, response to treatment and blood test results. Azathioprine does not work immediately and it may be many months before you notice any benefit. It is very important that you have blood tests every week for the first four weeks and every three months thereafter. However, this may need to be done more frequently depending upon blood test results. You may need to reduce the dose of azathioprine or temporarily stop treatment depending upon your blood test results. You must not take azathioprine unless you are having regular blood tests. If you have not had blood tests as planned it is important to you contact your GP or hospital doctor. 5 6 G W. Design Services, Salford Royal NHS Foundation Trust, All Rights Reserved Document for issue as handout. Unique Identifier: NOE 16 (16). Review date: April 2018.

5 How long will I continue on treatment and what should I do if I forget to take my tablets? You may need to stay on azathioprine for many years. If you forget to take your medication you should not take the missed dose or double your next dose. Instead, you should take your next dose as usual. If you have forgotten to take your medication on more than a few occasions, it is very important to tell your doctor as this information may influence the dose you are prescribed in future. What happens if I decide not to start treatment? You will have the opportunity to ask your hospital doctor questions about the information in this leaflet before you decide whether or not to start treatment. If you decide not to start treatment your future care will not be affected in any way. However, your hospital doctor will need to discuss the likely consequences of this decision and other treatment options. If you agree to start treatment you are free to stop at any time. However, it is very important that you discuss this with your hospital doctor beforehand as this is likely to have an adverse effect on your condition. Advice once started on treatment For routine advice please contact your hospital doctor, nurse or GP. For emergency advice you should contact your GP who will be able contact the on-call neurology service at Salford Royal or your hospital doctor if needed. Local contacts Name Telephone number References Current Summary of Product Characteristics British National Formulary UK Teratology Information Service G W. Design Services, Salford Royal NHS Foundation Trust, All Rights Reserved Document for issue as handout. Unique Identifier: NOE 29 (14). Review date: May 2016.

6 W. Design Services Salford Royal NHS Foundation Trust All Rights Reserved 2016 This document MUST NOT be photocopied University Teaching Trust Information Leaflet Control Policy: Unique Identifier: NOE 16 (16) Review Date: April 2018 For further information on this leaflet, it s references and sources used, please contact Copies of this information are available in other languages and formats upon request. If you need this interpreting please telephone In accordance with the Equality Act we will make reasonable adjustments to enable individuals with disabilities, to access this treatment / service. InterpretationandTrans@srft.nhs.uk Under the Human Tissue Act 2004, consent will not be required from living patients from whom tissue has been taken for diagnosis or testing to use any left over tissue for the following purposes: clinical audit, education or training relating to human health, performance assessment, public health monitoring and quality assurance. If you object to your tissue being used for any of the above purposes, please inform a member of staff immediately. Salford Royal operates a smoke-free policy. For advice on stopping smoking contact the Hospital Specialist Stop Smoking Service on Salford Royal NHS Foundation Trust Stott Lane, Salford, Manchester, M6 8HD Telephone If you would like to become a Foundation Trust Member please visit: for-members If you have any suggestions as to how this document could be improved in the future then please visit: for-patients