Gastroenterology Azathioprine and 6-Mercaptopurine Information
What they are Azathioprine and 6-mercaptopurine are used in the treatment of inflammatory bowel disease. They are often prescribed when steroids have not been able to bring the condition under control. Azathioprine has effects on the immune system (the body's own defence system). One of its actions is to reduce the activity of the immune system, so it is always used with care. Doctors may prescribe it for people on steroid treatment so their steroid dose can be smaller. Azathioprine is more commonly known by brand (trade) names, e.g Imuran. It is important to keep to the same brand unless your doctor advises otherwise. 6- mercaptopurine is known as Puri-Nethol. Please note that this sheet does not list all the uses and side-effects associated with this medicine. For full details please see the information leaflet which comes with your medicine. Your doctor will assess your medical circumstances and draw your attention to any information or side-effects, which may be relevant in your particular case. 2
What they do Azathioprine and 6-mercaptopurine can reduce inflammation by suppressing the disease process. In bowel diseases, damage to the bowel is reduced. When and how do I take my tablets? Azathioprine and 6-mercaptopurine can be taken as a single dose in the evening, or in divided doses with meals. What dose do I take? Your doctor will advise you. Usually you will start on a low dose (e.g 50mg per day) and your doctor may increase this if necessary. The dose you are given will depend on your body weight. Seeing the benefits Azathioprine and 6-mercaptopurine do not work immediately. It may be 12-20 weeks before you notice any benefit. 3
Take care! Store azathioprine and 6-mercaptopurine tablets below 25 C, in a safe place out of the reach of children and pets. Store the tablets away from light. If your treatment ends and you have some tablets left over, return them to your pharmacist. Do not flush them down the toilet or throw them away. If you miss a dose If you forget to take a dose, take another one as soon as you remember, unless it is almost time for your next dose. Do not double the dose. If you take too much azathioprine or 6-mercaptopurine tell your doctor immediately. If you take too many tablets If you take too many tablets, note how many tablets you have taken and call your doctor immediately or go to the nearest hospital casualty department taking the labelled medicine container with you. 4
If you feel sick If you feel sick and/or vomit within a few hours of taking azathioprine or 6-mercaptopurine, tell your doctor. Do not take another dose until the next dose is due. If you develop a sore throat or chest infection please inform your doctor. However, if you are suffering with simple coughs or colds (that is, you do not have a fever) you should continue to take your azathioprine. What are the possible side-effects? These drugs are an important part of the treatment of patients with inflammatory bowel disease, but a small number of patients may experience side-effects that will prevent them from continuing with treatment. There are no special problems for children taking these medicines. Lower doses of these drugs may be used in patients aged over 60 years, as there may be a slightly increased risk of side-effects. If you develop any new symptoms after starting these medicines, you should tell your hospital consultant or GP as soon as possible. If any of these symptoms are severe, you should stop azathioprine or 6- mercaptopurine and see your doctor immediately. 5
Immediate side-effects (within 48 hours) Tell your doctor if these symptoms persist or occur after every dose: Sickness and loss of appetite Abdominal pain if this develops, the drug should be stopped immediately Skin rashes, fever (rare) Delayed side-effects (within 2-3 weeks) Hair loss Long term side-effects (these side effects are rare) Jaundice (rare) Bone marrow damage your regular blood count test will check how well your bone marrow is working. If your bone marrow becomes damaged you might suffer from anaemia, catch infections regularly and bruise or bleed easily. There is a slightly increased risk of certain types of cancer with azathioprine and 6-mercaptopurine treatment, e.g. skin cancers. Sunscreens and/or protective clothing should be worn to reduce sunlight exposure. Please discuss this with your doctor if you have any concerns about this. 6
Things to tell your doctor immediately Severe and continuing sickness, or stomach pains Unexplained skin rash Yellowing of the skin or generalised itching Infections including fever, chills or sore throats Bleeding gums, black tarry stools or unexpected bleeding or bruising. If you develop chickenpox or shingles, or if you have never had chickenpox and come into contact with someone who has chickenpox or shingles, you should stop taking azathioprine or 6-mercaptopurine and see your doctor immediately as you may need special treatment. Chickenpox and shingles can be severe in people on treatment such as azathioprine or 6-mercaptopurine which affect the immune system, and you may require anti-viral treatment. Why you need regular blood tests It is important that you do not miss your blood test. You must not take azathioprine or 6-mercaptopurine unless you are having regular blood tests every 4 weeks. The results tell your doctor how well the azathioprine or 6-7
mercaptopurine is working and will also show if you are developing any side-effects. If your blood or liver is being affected, your treatment will be changed or stopped. Your kidney function will also be checked from time to time. In most patients, levels of the enzyme thiopurine methyltransferase (TMPT) are checked prior to starting these drugs and if the level is low, the drug may not be suitable for these patients due higher risk of bone marrow suppression. The testing will be supervised by your gastroenterology specialist team or in a shared care arrangement with your GP. When you start taking azathioprine or 6-mercaptopurine, your doctor will give you a booklet in which your attendance for blood tests and changes to your dose will be recorded. This will help your doctor and pharmacist be sure that the dose is right for you and not adversely affecting your body. It will help you be sure you are taking the right dose. Always show the booklet to any doctor, nurse, pharmacist or dentist caring for you. 8
Can I take other medicines along with azathioprine or 6-mercaptopurine? Always check with your doctor or pharmacist before taking any other medicine; always show your booklet to the pharmacist or tell them you are taking azathioprine or 6-mercaptopurine. This includes medicines you can buy without prescription (such as aspirin, paracetamol and other painkillers), medicines for coughs, colds and flu and herbal or alternative medicines. These may contain ingredients that react with azathioprine or 6- mercaptopurine and which could affect your treatment. Also, the symptoms you are trying to treat may be a sign of the azathioprine or 6-mercaptopurine not working for you as it is meant to. Keep a record of any symptoms in your booklet and discuss them with your doctor. Azathioprine or 6-mercaptopurine may be prescribed along with other medicines to treat your condition. Some drugs interact with these medicines, for example, allopurinol (used in the treatment of gout), the blood thinning treatment warfarin and certain antibiotics (cotrimoxazole and trimethoprim). You should discuss any new medications with your doctor before starting them, and you should always tell any other doctor treating you that you are taking azathioprine or 6-mercaptopurine. 9
Azathioprine and 6-mercaptopurine are not painkillers, so if you are taking any painkillers you may continue to take these as well as ciclosporin, unless your doctor advises otherwise. Can I have immunisations while on azathioprine or 6- mercaptopurine? It is recommended that you should not be immunised using any of the live vaccines such as polio, yellow fever, measles, mumps, BCG, oral typhoid or rubella (German Measles). However, in certain situations a live vaccine may be indicated (for example rubella immunisation in women of childbearing age), in which case your doctor will discuss the possible risks and benefits of the immunisation with you. Pneumovax and yearly 'flu vaccines are safe and recommended. Can I drive while taking azathioprine or 6- mercaptopurine? Avoid driving, hazardous work and operating machinery until you have learnt how azathioprine or 6- mercaptopurine affects you as these drugs occasionally can cause dizziness. 10
May I drink alcohol while taking azathioprine or 6- mercaptopurine? If you drink alcohol you should only drink it in moderation because these medicines can affect the liver. Your doctor can give you more information and advice about this. Fertility, pregnancy and breastfeeding It is best not to take azathioprine or 6-mercaptopurine when pregnant. However, sometimes this may be unavoidable. From experience the drug appears to be safe in pregnancy, but a detailed discussion with your doctor will help you come to a decision about continuation of the drug in pregnancy There is a chance that the normal development of a baby can be affected if either the mother or the father is exposed to azathioprine or 6-mercaptopurine. If you are planning a family or if you, or your partner, become pregnant while taking azathioprine or 6-mercaptopurine you should discuss this with your doctor as soon as possible. Women should not breastfeed while taking azathioprine or 6-mercaptopurine. 11
Where can I obtain further information? If you would like any further information about azathioprine or 6-mercaptopurine, or if you have any concerns about your treatment, particularly in relation to cultural or lifestyle needs, you should discuss this with your hospital consultant, GP or pharmacist. Contact Information If you need to contact your Consultant please speak with one of the Gastroenterology Nurse Specialists on the number listed below. If no one is available to take your call please leave a message on the answer phone. 01536 493353 / 01536 492252 If you need this information in another format or language, please telephone 01536 492510. Further information about the Trust is available on the following websites: KGH - www.kgh.nhs.uk NHS Choices - www.nhs.uk Ref: PI.379 December 2013 Review: September 2015