Foster Special Precautions

The drug should be used with caution (which may include monitoring) in patients with cardiac arrhythmias, especially third degree atrioventricular block and tachyarrhythmias (accelerated and/or irregular heart beat), idiopathic subvalvular aortic stenosis, hypertrophic obstructive cardiomyopathy, severe heart disease, particularly acute myocardial infarction, ischaemic heart disease, congestive heart failure, occlusive vascular diseases, particularly arteriosclerosis, arterial hypertension and aneurysm.
Caution should also be observed when treating patients with known or suspected prolongation of the QTc interval, either congenital or drug induced (QTc >0.44 seconds). Formoterol itself may induce prolongation of the QTc interval.
Caution is also required when the drug is used by patients with thyrotoxicosis, diabetes mellitus, phaeochromocytoma and untreated hypokalaemia.
Potentially serious hypokalaemia may result from beta₂-agonist therapy. Particular caution is advised in severe asthma as this effect may be potentiated by hypoxia. Hypokalaemia may also be potentiated by concomitant treatment with other drugs which can induce hypokalaemia, such as xanthine derivatives, steroids and diuretics. Caution is also recommended in unstable asthma when a number of "rescue" bronchodilators may be used. It is recommended that serum potassium levels are monitored in such situations.
The inhalation of formoterol may cause a rise in blood glucose levels. Therefore blood glucose should be closely monitored in patients with diabetes.
If anaesthesia with halogenated anaesthetics is planned, it should be ensured that the drug is not administered for at least 12 hours before the start of anaesthesia as there is a risk of cardiac arrhythmias.
As with all inhaled medication containing corticosteroids, the drug should be administered with caution in patients with active or quiescent pulmonary tuberculosis, fungal and viral infections in the airways.
It is recommended that treatment with the drug should not be stopped abruptly.
If patients find the treatment ineffective medical attention must be sought. Increasing use of rescue bronchodilators indicates a worsening of the underlying condition and warrants a reassessment of the asthma therapy. Sudden and progressive deterioration in control of asthma or COPD is potentially life-threatening and the patient should undergo urgent medical assessment. Consideration should be given to the need for increased treatment with corticosteroids, either inhaled or oral therapy, or antibiotic treatment if an infection is suspected.
Patients should not be initiated on the drug during an exacerbation, or if they have significantly worsening or acutely deteriorating asthma. Serious asthma-related adverse events and exacerbations may occur during treatment with the drug. Patients should be asked to continue treatment but to seek medical advice if asthma symptoms remain uncontrolled or worsen after initiation on the drug.
As with other inhalation therapy paradoxical bronchospasm may occur with an immediate increase in wheezing and shortness of breath after dosing. This should be treated immediately with a fast-acting inhaled bronchodilator. The drug should be discontinued immediately, the patient assessed and alternative therapy instituted if necessary. The drug should not be used as the first treatment for asthma.
For treatment of acute asthma attacks patients should be advised to have their short-acting bronchodilator available at all times.
Patients should be reminded to take the drug daily as prescribed even when asymptomatic.
Once asthma symptoms are controlled, consideration may be given to gradually reduce the dose of the drug. Regular review of patients as treatment is stepped down is important. The lowest effective dose of the drug should be used.
Systemic effects may occur with any inhaled corticosteroid, particularly at high doses prescribed for long periods. These effects are much less likely to occur with inhaled than with oral corticosteroids. Possible systemic effects include: Cushing's syndrome, Cushingoid features, adrenal suppression, decrease in bone mineral density, growth retardation in children and adolescents, cataract and glaucoma.
Therefore, it is important that the patient is reviewed regularly, and the dose of inhaled corticosteroid is reduced to the lowest dose at which effective control of asthma is maintained.
Effects on Ability to Drive and Use Machines: The drug is unlikely to have any effect on the ability to drive and operate machinery.