BMA Concise Guide to Medicine & Drugs

Terbutaline

Brand name Bricanyl

Used in the following combined preparations None

QUICK REFERENCE

Drug group Bronchodilator

Overdose danger rating Low

Dependence rating Low

Prescription needed Yes

Available as generic Yes

GENERAL INFORMATION

Terbutaline is a sympathomimetic bronchodilator used to treat conditions such as asthma, chronic obstructive pulmonary disease (COPD) and bronchospasm, in which the airways become constricted. Terbutaline is also used to delay premature labour.

Muscle tremor, especially of the hands, is common with terbutaline and usually disappears on reduction of the dose or with continued use as the body adapts to the drug. In common with the other sympathomimetic drugs, it may produce nervousness and restlessness.

INFORMATION FOR USERS

Your drug prescription is tailored for you. Do not alter dosage without checking with your doctor.

How taken/used Tablets, liquid (syrup), injection, inhaler, nebules for nebulizer.

Frequency and timing of doses 3 x daily (tablets/syrup); as necessary (inhaler).

Dosage range Adults 7.5–15mg daily (tablets/syrup); 0.5mg when required, up to 2mg daily (inhaler); as directed by doctor (nebules). Children Reduced dose according to age and weight.

Onset of effect Within a few minutes (inhaler); within 1–2 hours (tablets/syrup).

Duration of action 7–8 hours (tablets/syrup).

Diet advice None.

Storage Keep in original container at room temperature out of the reach of children. Protect from light. Do not puncture or burn aerosol containers.

Missed dose Do not take the missed dose. Take your next dose as usual.

Stopping the drug Do not stop the drug without consulting your doctor; symptoms may recur.

Exceeding the dose An occasional unintentional extra dose is unlikely to be a cause for concern. But if you notice any unusual symptoms, or if a large overdose has been taken, notify your doctor.

POSSIBLE ADVERSE EFFECTS

Muscle tremor, which particularly affects the hands, anxiety, and restlessness are the most common adverse effects of terbutaline. Discuss with your doctor if they are severe or if you experience headaches or muscle cramps. If you have palpitations, you should stop using the drug and consult your doctor. Rarely, wheezing or breathlessness may worsen immediately after inhaler use (paradoxical bronchospasm). If this happens, stop using the drug and contact your doctor immediately.

INTERACTIONS

Other sympathomimetics may add to the effects of terbutaline and vice versa, so increasing the risk of adverse effects.

Monoamine oxidase inhibitors (MAOIs) Terbutaline may interact with these drugs to cause a dangerous rise in blood pressure.

Diuretics, corticosteroids, and theophylline taken with terbutaline may reduce blood levels of potassium, causing muscle weakness.

Beta blockers may reduce the beneficial effects of terbutaline.

SPECIAL PRECAUTIONS

Be sure to tell your doctor if:

· You have heart problems.

· You have high blood pressure.

· You have an overactive thyroid.

· You are taking other medicines.

Pregnancy Safety in early pregnancy not established, although it is used in late pregnancy to prevent premature labour. Discuss with your doctor.

Breast-feeding The drug passes into the breast milk but in amounts too small to affect the baby.

Infants and children Reduced dose necessary.

Over 60 Increased likelihood of adverse effects. Reduced dose may therefore be necessary.

Driving and hazardous work Avoid such activities until you have learned how terbutaline affects you because the drug can cause tremor of the hands.

Alcohol No special problems.

PROLONGED USE

No problems expected. However, you should contact your doctor if you find you are needing to use your terbutaline inhaler more than usual. Failure to respond to the drug may be a result of worsening asthma that requires urgent medical attention.

Monitoring Periodic blood tests for potassium may be needed in people on high-dose treatment with terbutaline combined with other asthma drugs.