How does it work?

Bricanyl injection contains the active ingredient terbutaline, which is a type of medicine known as a short-acting beta 2 agonist. (NB. Terbutaline is also available without a brand name, ie as the generic medicine.)

Terbutaline is given as an injection or as a drip (infusion) to treat two very different conditions. Firstly, it may be given in hospital to treat severe narrowing of the airways that is causing difficulty breathing (bronchospasm). This might be due to a severe asthma attack, chronic obstructive pulmonary disease (COPD, eg emphysema and chronic bronchitis), or a severe allergic reaction. Secondly, it can be used to help stop premature labour.

Terbutaline works by acting on receptors called beta 2 receptors. These are found in the lungs and the uterus (womb).

When terbutaline stimulates the beta 2 receptors in the lungs, it causes the muscles in the airways to relax. This allows the airways to open and so makes it easier to breathe.

When terbutaline stimulates the beta 2 receptors in the uterus, it causes the muscles in the walls of the uterus to relax. This can stop the contractions associated with premature labour. Terbutaline can be used to stop labour that starts between 24 and 33 weeks gestation. It usually delays delivery by at least 48 hours. This can give sufficient time to treat the mother with corticosteroids, or take other measures to improve the outcome for mother and baby, including moving the mother to a hospital with a neonatal intensive care unit.

What is it used for?

• Relieving severe bronchospasm (breathing difficulties), eg due to asthma or chronic obstructive pulmonary disease (COPD)
• Stopping uncomplicated premature labour

Warning!

• 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.
• Women receiving this medicine for premature labour should have their pulse rate monitored. The heart rate of the baby should also be monitored.

Use with caution in

• Diabetes
• Heart failure
• Heart disease
• High blood pressure (hypertension)
• Irregular heart beats (arrhythmias)
• Thyrotoxicosis

Not to be used in

• Known sensitivity or allergy to any ingredient

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.

• This medicine should be used with caution during pregnancy, particularly during the first trimester, and only if the expected benefit is greater than any possible risk to the foetus. Seek medical advice from your doctor.
• The medicine passes into the breast milk, but at normal doses it is unlikely to harm the baby. Discuss with your doctor.

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.

• Shaking, usually of the hands (tremor)
• Headache
• Nausea
• Awareness of your heart beat (heart palpitations)
• Muscle cramps
• Tense feeling
• Sleep disturbances
• Increased heart rate (tachycardia)
• Low blood potassium level (hypokalaemia)
• Pulmonary oedema (fluid in the lungs) in the mother (when used for premature labour). Cough and shortness of breath are symptoms of this, if you experience these you should tell the doctor immediately.

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, so they can check that the combination is safe.

This medicine should not be taken with beta-blockers, such as atenolol, propranolol or timolol. This is because beta-blockers have an opposite action to this medicine and cause the airways to narrow. This can result in breathing difficulties for people with asthma or COPD. This problem has sometimes been seen with eye drops containing beta-blockers, eg used for glaucoma.

Terbutaline can potentially cause a serious decrease in the levels of potassium in the blood (hypokalaemia), which may result in adverse effects. This effect can be increased by the following medicines, which can also lower potassium in the blood:

• xanthine derivates, such as theophylline or aminophylline
• corticosteroids, such as beclometasone and prednisolone
• other beta 2 agonists, such as salmeterol
• diuretics, such as bendrofluazide and frusemide.

This is why people with severe asthma or COPD, who may be taking several of these medicines, should have their blood potassium levels monitored regularly.

Other medicines containing the same active ingredient

Terbutaline syrup and inhalation solution (respules) are also available without a brand name, ie as the generic medicine.