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" What is it used for?   Asthma.  Chronic obstructive pulmonary disease (COPD).  How does it work? Nuelin SA prolonged-release tablets contain the active ingredient theophylline. Theophylline is a type of medicine called a xanthine bronchodilator. It is used to open the airways.  Theophylline causes the muscles surrounding the airways to relax by a mechanism that is not fully understood. This allows the airways in the lungs to open. In conditions where the airways tighten, such as asthma or chronic obstructive pulmonary disease (COPD, eg emphysema and chronic bronchitis), it is difficult for air to get in and out of the lungs. By opening the airways, theophylline makes it easier to breathe. Nuelin SA tablets are designed to release the theophylline slowly over 12 hours. They are taken as a regular twice daily treatment to help keep the airways relaxed and open all the time.  How do I take it?  Nuelin SA tablets should be taken regularly, twice a day, 12 hours apart. The strength of tablets prescribed and number of tablets to take will vary from person to person. Follow the instructions given by your doctor. These will also be printed on the dispensing label that your pharmacist has put on the packet of medicine. The tablets should preferably be taken after food.  The tablets should be swallowed whole with a drink of water. Do not crush or chew the tablets as this will cause the whole dose of theophylline to be released and absorbed into the body at once. This can be dangerous and could potentially result in an overdose. (Nuelin SA 250 tablets are scored and may be broken in half for swallowing, but they should not be crushed or chewed.) Try to always take your tablets at the same times each day as this will help you remember to take them. If you forget to take a dose at your usual time don&amp;#039;t worry, just leave out that dose and take your next dose as usual when it is due. Do not take a double dose to make up for a missed dose.  Warning!  There is a narrow margin between the blood level of theophylline that is needed for the medicine to be effective and the blood level that is high enough to cause side effects. Your doctor may need to take a blood test to monitor your theophylline level from time to time, to make sure that you are taking the right dose to put you within the correct range.  Acute viral infections can increase your theophylline blood level. You should consult your doctor if you get a feverish infection, so that if necessary your theophylline blood level can be checked. Smoking tobacco or cannabis, chewing tobacco or taking snuff can increase the removal of theophylline from the body and so decrease your theophylline blood level. You should tell your doctor if you are a smoker, as you may need a higher than normal dose of theophylline. You should also tell your doctor if you are giving up smoking, as this may mean your dose will need reducing.  If this medicine doesn&amp;#039;t seem to work as well, or for as long as usual, or you need to use your reliever inhaler (eg salbutamol or terbutaline) more often than usual to relieve wheezing or chest tightness, you should consult your doctor as soon as possible. It may be that your asthma or COPD is getting worse and your doctor might need to give you another medicine.  People with severe asthma should have regular blood tests to monitor the amount of potassium in their blood. This is because low oxygen levels in the blood (hypoxia) and various asthma medicines, including this one, can lower blood potassium levels.   Not to be used in  People who are allergic to other xanthines, eg aminophylline, caffeine. People with rare inherited blood disorders called porphyrias. Nuelin SA tablets are not recommended for children under six years of age. Other forms of theophylline are available for younger children - see end of page.  This medicine should not be used if you are allergic to one or any of its ingredients. Please inform your doctor or pharmacist if you have previously experienced such an allergy. If you feel you have experienced an allergic reaction, stop using this medicine and inform your doctor or pharmacist immediately. Use with caution in  Elderly people. People with impaired liver function. People with heart disease such as heart failure or an irregular heartbeat (arrhythmia). People with high blood pressure (hypertension). People with an overactive thyroid gland (hyperthyroidism). People with a peptic ulcer. People with epilepsy.  Chronic alcoholism. People with a viral infection - see warning section above.  Pregnancy and breastfeeding Certain medicines should not be used during pregnancy or breastfeeding. However, other medicines may be safely used in pregnancy or breastfeeding providing the benefits to the mother outweigh the risks to the unborn baby. Always inform your doctor if you are pregnant or planning a pregnancy, before using any medicine.  It is important that asthma is well controlled in pregnant women because severe asthma attacks can be dangerous to the pregnancy. Expert opinion is that theophylline can usually be taken as normal during pregnancy, however it is important to get advice from your doctor if you think you could be pregnant. Use of theophylline during late pregnancy may be associated with irritability in the newborn baby. The manufacturer states that this medicine should only be used during pregnancy if the benefits outweigh any possible risks to the baby. Ask your doctor for more advice. This medicine passes into breast milk and has been associated with irritability and fretful sleep in breast-fed infants. The manufacturer states that this medicine should only be used in women who are breastfeeding if the benefits to the mother outweigh any risks to the nursing infant. However, expert opinion is that theophylline can usually be taken as normal during breastfeeding, providing the baby is monitored for possible side effects. It is important to get medical advice from your doctor before breastfeeding while using this medicine.   Side effects Medicines and their possible side effects can affect individual people in different ways. The following are some of the side effects that are known to be associated with this medicine. Just because a side effect is stated here, it does not mean that all people using this medicine will experience that or any side effect.  Nausea and vomiting. Stomach irritation. Diarrhoea. Increased heart rate (tachycardia). Awareness of your heartbeat (palpitations). Irregular heartbeats (arrhythmias). Headache. Restlessness, agitation or anxiety. Difficulty sleeping (insomnia). Fits (convulsions). Low blood potassium level (hypokalaemia).  The side effects listed above may not include all of the side effects reported by the medicine&amp;#039;s manufacturer. For more information about any other possible risks associated with this medicine, please read the information provided with the medicine or consult your doctor or pharmacist. How can this medicine affect other medicines? It is important to tell your doctor or pharmacist what medicines you are already taking, including those bought without a prescription and herbal medicines, before you start treatment with this medicine. Similarly, check with your doctor or pharmacist before taking any new medicines while taking this one, to make sure that the combination is safe.  Children must not take ephedrine (a decongestant found in some cough and cold remedies) while taking theophylline, as there may be an increased risk of side effects with the combination. The following medicines may increase the blood level of theophylline; your doctor may need to reduce your theophylline dose if you take any of these in order to avoid side effects:  aciclovir allopurinol calcium-channel blockers, eg diltiazem, verapamil, nifedipine  cimetidine contraceptives containing an oestrogen  deferasirox disulfiram fluconazole  flu vaccine (this is very unlikely to affect your theophylline level, but you should tell your doctor if you notice any new or increased side effects after having a flu vaccine) fluvoxamine interferon alfa isoniazid macrolide type antibiotics, eg erythromycin, clarithromycin  methotrexate mexiletine pentoxifylline propafenone quinolone type antibiotics, eg ciprofloxacin, enoxacin, norfloxacin.  The following medicines may decrease the blood level of theophylline; your doctor may need to increase your theophylline dose if you take any of these, in order to make sure the theophylline is effective:   carbamazepine barbiturates such as phenobarbital  phenytoin primidone rifampicin ritonavir the herbal remedy St John&amp;#039;s wort (Hypericum perforatum).  Theophylline may decrease the blood levels of the following medicines, which may reduce their effects:  lithium phenytoin  carbamazepine.  Theophylline may increase the blood level of the medicine roflumilast used to treat COPD. Theophylline is not recommended for use in combination with roflumilast.  Theophylline should not normally be taken with beta-blockers such as propranolol, as these can cause the airways to narrow, thus opposing the effects of theophylline. There may be an increased risk of seizures if ketamine or quinolone-type antibiotics such as ciprofloxacin are taken with theophylline. Theophylline may oppose the sedative effects of benzodiazepines, eg diazepam, temazepam, clonazepam. The level of thyroid hormones in the body affects the way the body handles theophylline. If you have high thyroid hormone levels and start treatment to lower them, eg with medicines such as carbimazole, propylthiouracil or radioactive iodine, your doctor may decrease your theophylline dose. If you have low thyroid hormone levels and start treatment with thyroxine, your doctor may increase your theophylline dose. Theophylline may potentially decrease the amount of potassium in the blood. If it is taken in combination with any of the following medicines, which can also lower potassium in the blood, the risk of a low blood potassium level (hypokalaemia) is increased:  acetazolamide corticosteroids, such as beclometasone and prednisolone  beta 2 agonists, such as salbutamol and salmeterol  diuretics, such as bendroflumethiazide and furosemide.  A low blood potassium level can have serious effects, which is why people with severe asthma, who may be taking several of these medicines, should have their blood potassium level monitored regularly. Sucralfate may reduce the absorption of theophylline from the gut and should not be taken within two hours of taking theophylline. Other medicines containing the same active ingredient   Slo-phyllin.  Uniphyllin continus.  Theophylline is absorbed into the body at different rates from different brands of prolonged-release theophylline. This could either reduce the effect of the medicine or increase the effect of the medicine and increase the risk of side effects. For this reason different brands of theophylline are not interchangeable. You should make sure you know which brand of theophylline you normally take and that you receive the correct brand each time your prescription is dispensed. You should check with your pharmacist if you are ever dispensed a brand that you are not expecting.  Last updated 08.07.2014 "^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.netdoctor.co.uk/medicines/allergy-and-asthma/a7243/nuelin-sa-theophylline/>