Patient Information Leaflet Intron A Injection What is Intron A Intron A contains a substance known as alfa interferon. Alfa interferons are proteins which are normally produced by the body to help defend itself against viruses. As well as anti-viral properties, alfa interferons can slow down the development of some types of cancer cells. What type of medicine is it? Intron A is an alfa interferon used to treat some viral infections and certain types of cancer. It cannot be taken by mouth since it would be broken down by enzymes in the gut. It must therefore be administered by injection. The dose is measured in International Units (IU). What do vials of Intron A contain? Powder vials contain either 3, 5 or 10 million IU of interferon alfa-2b(rbe).They also contain the following inactive ingredients: glycine, sodium phosphate dibasic, sodium phosphate monobasic and human albumin. Product Licence Holder: Schering-Plough Ltd, Welwyn Garden City, Hertfordshire AL7 1TW. Manufactured by: Schering-Plough (Briny) Co., Innishannon, County Cork, Ireland. When is Intron A used? Intron A is used to treat a n umber of different cancers and viral infections. These are: Hairy Cell Leukaemia: a very rare type of cancer of the blood Chronic myelogenous leukaemia: a cancer of the blood Multiple myeloma: a cancer of the bone marrow Non-Hodgkin's Lymphoma: a cancer of the lymph glands AlDS-related Kaposi's sarcoma: a rare skin tumour which can develop in patients with AIDS. Hepatitis B: a viral infection of the liver Chronic Hepatitis C/Non-A, Non-B: a viral infection of the liver Condylomata acuminata: genital warts caused by a viral infection Your doctor will explain to you which of these conditions you have. Are there any people who should not be treated with Intron A? You should not be treated if you:
Children are not normally treated with Intron A unless the doctor thinks that it is essential. You should not take Intron A if you have certain types of long-term liver disease e.g. cirrhosis (check with your doctor if you are not sure). It may be necessary to carry out tests during treatment At intervals whilst receiving Intron A therapy and prior to starting treatment your blood will be tested. In addition, if you are being treated for Hepatitis B you may also need a special liver test (a liver biopsy). Are there any other reasons why Intron A should not be used? If you are pregnant or breast-feeding a baby you should only be treated with Intron A if you have discussed with your doctor whether the benefits of the medicine for you, the mother, outweigh any possible risks to the child. If you are of child-bearing age, you should use contraceptives during treatment. |
What would happen if you were allergic to Intron A? Very rarely, some patients have allergic reactions following their first injection. This could be in the form of a severe, red or itchy rash, difficulty in breathing, or shock. Your doctor will then stop your treatment. Should Intron A be stopped for any other reason? If you have any of the following illnesses before treatment, or develop them whilst on treatment, you r doctor may need to reduce your dose of Intron A, or you may need extra treatment to control them. Your doctor will decide by watching the signs and symptoms carefully, doing tests if necessary. In some cases it may be necessary to stop Intron A altogether.
If you notice any changes in your eyesight whilst you are taking Intron A, you should tell your doctor as he may wish to perform an eye examination. Are there any medicines which should not be given at the same time as Intron A? Sleeping tablets, medicines taken for anxiety (sedatives) and strong pain killers should not be taken during treatment unless you have checked with your doctor first. You can take 1-2 paracetamol 500 mg tablets, 30 minutes before injection if you need to, but remember not to exceed 8 tablets in any 24 hours. Certain asthma drugs, called theophylline or aminophylline, may need a change in dosage during Intron A treatment What is the dose? The dose you are given depends on how big you are. It varies with your body surface area. Technically, this is measured in square metres (m2), but actually it is worked out from your weight and height. There are also different doses according to the disease being treated. Sometimes doctors prescribe different doses to those shown below. For example, your doctor may prescribe you a different dose of Intron A if you are already taking another medicine to treat your disease. If this applies to you, you can discuss it with your doctor, if you have not already done so. How is Intron A given? Usually by subcutaneous injection. This means Intron A is injected with a short needle into the fatty tissue just under the skin. It is given either daily or three times a week on every other day, for example, on Mondays, Wednesdays and Fridays. For genital warts, the injection is made directly into the base of the wart. A local anaesthetic may be administered if it is uncomfortable. Disease treated Dose Hairy Cell Leukaemia: 2 million lU/m2 3 times a week for 6 months or more by subcutaneous injection Chronic 4 to 5 million IU/m2 daily until myelogenous the disease is under control leukaemia: then 3 times a week by subcutaneous injection Multiple myeloma 3 million IU/m2 3 times a week maintenance therapy: by subcutaneous injection Non-Hodgkin's 5 million IU 3 times a week for Lymphoma: 18 months by subcutaneous injection AlDS-related Usually 30 million IU/m2 3 to 5 Kaposi's sarcoma: times a week by subcutaneous injection or by injection into the muscle |
Disease treated Dose Hepatitis B: Usually 2.5 to 5 million lU/m2 3 times a week for 4 to 6 months by subcutaneous injection. Chronic Hepatitis C/ Usually 3 million IU 3 times a Non-A, Non-B: week for up to 18 months, by subcutaneous injection. Condylomata acuminata: 1 million IU injected into the base of each wart 3 times a week for 3 weeks. As many as 5 warts can be treated at one time. The total dose each week should not be more than 15 million IU. If you have more than 5 warts, a further course of treatment may be needed. What to do in case of overdose Contact your doctor as soon as possible. Many patients give injections themselves at home As Intron A is usually given daily or 3 times a week, it is usually more convenient to have injections at home. You can give subcutaneous injections yourself. These injections are simple to do and you will be shown how to do them. Sometimes a relative, friend or community nurse could do them for you. Preparing for an Injection
Preparing an injection
Giving the subcutaneous injection
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push it firmly and quickly into the pinched skin. Draw back the plunger to check that no blood appears. If blood comes up into the syringe, remove needle and press cotton wool firmly over the injection site to stop any bleeding. When ready start again at 3.
What to do if you forget to inject Intron A Inject your recommended dose as soon as you remember and then carry on as normal. Are there any side-effects Like all drugs, Intron A has side effects. Although a lot of different side effects have been seen, you should remember that most of them only rarely occur. Side effects are generally dose related and get better when treatment is stopped. The most common side effects are "flu-like" symptoms, such as fever, fatigue and headache. These symptoms are similar to those experienced when you catch flu and the body produces interferon naturally to fight off the virus. The feverish symptoms are most likely to occur 2 to 6 hours after the first few injections. After 2 weeks or so they are likely to disappear. Injecting Intron A about 2 hours before bedtime and taking 1-2 paracetamol 500 mg tablets 30 minutes before the injection and again when you go to bed will help alleviate the symptoms. Remember not to take more than 8 tablets in any 24 hour period. You may go on feeling tired after the first few weeks of Intron A therapy. If this is the case, take plenty of rest and pace your activities. You may also suffer from nausea and lose your appetite. You may occasionally suffer from some less common side-effects, such as: vomiting, diarrhoea, joint pain and weakness, sleepiness, dizziness, dry mouth, hair loss, back pain, depression, increased sweating, taste alteration, irritability, difficulty sleeping, confusion, difficulty in concentrating and low blood pressure. The following side-effects only occur rarely in a few patients being treated with Intron A: abdominal pain, rash, nervousness, problems at the site of injection e.g. inflammation or redness, Herpes simplex e.g. cold sores, itching, eye pain, anxiety, nose bleeds, coughing, sore throat, chest problems, pneumonia, inflammation of the lungs, drowsiness, loss of weight, swelling of the face, difficulty breathing, indigestion, irregular heart beat, high blood pressure, increased appetite, decreased sex drive, bleeding of the gums, problems with your eyesight. Intron A may also have an effect on the thyroid gland and cause high blood sugar. If you are having laboratory tests performed on your blood and urine, Intron A may cause abnormal results. Very rarely, a few people have had fits after having high doses of Intron A. If you think you are suffering from these, or any other side effects, you should tell your doctor. How you should store your Intron A Intron A powder should be stored in a refrigerator at 2-8°C but can be stored at room temperature (below ! 25°C) for short periods e.g. when travelling long distances, but solutions which have been made up from the powder should be stored at 2-8 C in a refrigerator. You may keep the solution for 24 hours when you store it in a refrigerator. Do not use the solution after this time. Do not use Intron A after the expiry date which is stamped on the label. If there is anything you do not understand: You will see from this leaflet that Intron A is quite a complex medicine. If there is anything you do not understand, ask your doctor to explain it. Date of Revision: October 1995. |