Uniphyllin continus (Theophylline)

How does it work?

Uniphyllin continus 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.

Uniphyllin continus 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. The tablets should be swallowed whole, as crushing or chewing them will stop the prolonged release action from working.

Theophylline also stimulates the heart muscle, and Uniphyllin continus tablets are also licensed for treating heart failure.

What is it used for?

  • Asthma
  • Chronic obstructive pulmonary disease (COPD)
  • Heart failure


  • Different brands of prolonged release theophylline are not interchangeable, as they provide different blood levels of the medicine. 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.
  • Theophylline has a narrow margin between the blood level 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 taking the right dose to put you within the correct range.
  • 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. 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.
  • If this medicine doesn'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 can lower blood potassium levels.

Use with caution in

  • Elderly people
  • Heart failure
  • Irregular heart beats (arrhythmias)
  • Very high blood pressure (severe hypertension)
  • Hyperthyroidism
  • Peptic ulcer
  • Liver disease
  • Chronic alcoholism
  • Viral infections

Not to be used in

  • Allergy to xanthines, eg aminophylline, theophylline, caffeine
  • Life long inherited blood diseases which can cause a variety of symptoms, including mental health problems (porphyrias)
  • History of fits (seizures), eg epilepsy

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.

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.

  • The safety of this medicine during pregnancy has not been established, Its use during the third trimester may be associated with irritability in the baby. This medicine should only be used during pregnancy when the benefits outweigh any possible risks to the foetus. Seek medical advice from your doctor.
  • This medicine passes into breast milk and has been associated with irritability in the breast fed infant. Seek medical advice from your doctor before breastfeeding while using this medicine.

Label warnings

  • This medication is to be swallowed whole, not chewed.

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. 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
  • Increased heart rate (tachycardia)
  • Awareness of your heart beat (heart palpitations)
  • Headache
  • Restlessness
  • Difficulty in 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 drug'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 ensure that the combination is safe.

Children must not take ephedrine (a decongestant found in some cough and cold remedies) while taking theophylline.

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
  • disulfiram
  • flu vaccine
  • fluvoxamine
  • interferon alfa
  • isoniazid
  • quinolone type antibiotics, eg ciprofloxacin, enoxacin, norfloxacin
  • macrolide type antibiotics, eg erythromycin, clarithromycin
  • methotrexate
  • mexiletine
  • pentoxifylline
  • propafenone
  • propranolol
  • tiabendazole
  • ticlopidine
  • viloxazine.

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:

  • aminoglutethimide
  • antiepileptic medicines, such as phenytoin, carbamazepine
  • barbiturates
  • moracizine
  • rifampicin
  • rifabutin
  • ritonavir
  • sulfinpyrazone
  • the herbal remedy, St John's wort (Hypericum perforatum).

Theophylline may decrease the blood levels of the following medicines, which may reduce their effects:

  • alprazolam
  • lithium
  • phenytoin
  • carbamazepine.

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 a risk of seizures if ketamine is taken with theophylline.

Theophylline may oppose the sedative effects of benzodiazepines, eg diazepam, 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:

  • 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.

Other medicines containing the same active ingredient

Nuelin SA Slo-phyllin