SALBUTAMOL
Dosage form Tablets, 4mg, Syrup; 2 mg/ml -60 ml; Aerosol, 20 mg/10 ml -200 doses
Uses
Indications: Asthma bronchial, chronic bronchitis, pulmonary emphysema and relief of bronchospasm in asthma.
Properties: Salbutamol is a sympathomimetic bronchodilator, The bronchodilator activity of Salbutamol is very similar to that of isoprenaline, but the effects of Salbutamol on the cardiovascular system, although not negligible, are less than those of isoprenaline, Salbutamol has longer duration of action than isoprenaline, when given orally. After Salbutamol has been inhaled, it produces a rapid bronchodilator effect and at equi-active bronchodilator doses it produces a longer duration of effect than isoprenaline, with less likelihood of adverse cardiovascular effects.
Two distinct types of β-adrenergic receptors have been proposed: β1 in the myocardium and β2 in the bronchial and vascular smooth muscle. Stimulation of β1-receptors in the myocardium leads to tachycardia and increased cardiac output and stimulation of β2-receptors in the bronchi to bronchodilatation. Isoprenaline acts on both β1-receptors in the myocardium and β2-receptors in the bronchial and vascular smooth muscle. Salbutamol appears to have a selective action on β2-adrenergic receptors, but with a much greater specificity for receptors in the bronchial smooth muscle than in the vascular smooth muscle.
Administration
Dosage: Aerosol: 1 or 2 inhalations, repeated every four hours if required (one dose of aerosol contains 0.1 mg Salbutamol).
The oral dose for adults is 2 or 4 mg 3-4 times a day. The optimum single dose for many patients is 4 mg, but with elderly patients or with patients who are unusually sensitive to beta-adrenergic receptor stimulant substances it is advisable to start the treatment with 2 mg 3-4 times a day.
Children: From 2 to 6 year 1-2 mg 3-4 times a day; from 6 to 12 years 2 mg 3-4 times a day.
If necessary these doses may be cautiously increased.
Observe
Side effects: Nausea and headache may occasionally occur following both aerosol and oral dosage. Some patients have suffered from muscle tremor (usually hands) and palpitations after oral administration.
Contra-indications: So far no contra-indications have been found. Salbutamol should not be used together with other beta-blocking agents than those having selective 31-blocking effect.
Precaution: Use with caution for patients with myocardial insufficiency, hypertension or thyreotoxicosis. Like most drugs Salbutamol should not be used during the first three months of pregnancy. Patients should be warned of overdosage.
Children should be treated with a sympathomimetic aerosol only under the supervision of a responsible adult.
Storage Store in a cool and dry place, away from light. Keep out of reach of children. |
