|As a bronchodilator in the treatment of bronchospasm associated with bronchial asthma, emphysema and chronic bronchitis and other conditions associated with reversible airways obstruction. Salbutamol also decreases uterine contractility and arrests premature labor.
|Dosage & Administration:
|Adults: Usual Dose: 2-4 mg 3-4 times daily. Children 6-12 years: 2 mg 3 or 4 times daily; 2-6 years:1-2 mg 3 or 4 times daily.
Elderly patients should be given the lower dose initially.
|Fine tremor of skeletal muscles, tachycardia, palpitations and peripheral vasodilation may occur with salbutamol overdose. Treatment is symptomatic and supportive.
|Hyperthyroidism and cardiac disease. Salbutamol may interact with monoamine oxidase inhibitors and should not be given to patients receiving such treatment or within 14 days after stopping treatment.
Use in pregnancy & lactation: Safety in pregnancy and lactating women has not been established.
Salbutamol is not indicated for the prevention of premature labor associated with toxemia of pregnancy or ante partum hemorrhage, nor should it be used for threatened abortion during the 1st and 2nd trimesters of pregnancy.
|Tolerance may develop in asthmatic patients given salbutamol. If tolerance develops and the patient’s condition worsen, alternative or additional therapy should be instituted. The dosage of salbutamol should not be increased in these cases. Salbutamol should be avoided or used with care in patients undergoing anesthesia with any halogenated anesthetics.
|Salbutamol should be used with caution in patients with hyperthyroidism, cardiovascular disease, myocardial insufficiency, arrhythmias, susceptibility to QT-interval prolongation, occlusive vascular disorders, hypertension or aneurysm and diabetes mellitus. Hypokalemia associated with high doses of salbutamol may result in increased susceptibility to digitalis-induced cardiac arrhythmias. Tachyphylaxis with resistance may occur with prolonged use of high dosage. Caution is necessary when treating patients with diabetes mellitus or closed-angle glaucoma and in those receiving antihypertensive therapy. It is important to avoid excessive doses as this is thought to be linked to sudden death probably due to induction of ventricular arrhythmias.
|Salbutamol may cause fine tremor of skeletal muscle (particularly the hands), palpitations and muscle cramps. Tachycardia, nervous tension, hypokalemia, headaches and peripheral vasodilation have been reported after large doses. Anxiety, fever, restlessness, insomnia, confusion, irritability, weakness, psychotic states, decreased appetite, nausea and vomiting may occur due to the central effects of salbutamol. Difficulty in micturition and urinary retention, dyspnea, altered metabolism, sweating and hypersalivation may occur. Hypersensitivity reactions have occurred including paradoxical bronchospasm, angioedema, urticaria, hypotension and collapse.
|Use of salbutamol and other β2-agonist with corticosteroids, diuretics or xanthines increases the risk of hypokalemia and monitoring of potassium concentrations is recommended in severe asthma, where such combination therapy is the rule.
|Pregnancy Category (US FDA):
|Category C: Either studies in animals have revealed adverse effects on the foetus (teratogenic or embryocidal or other) and there are no controlled studies in women or studies in women and animals are not available. Drugs should be given only if the potential benefit justifies the potential risk to the foetus.
|Store at temperatures not exceeding 30°C.
|Mechanism of Action:
|Pharmacology: Pharmacokinetics: Salbutamol is readily absorbed from the gastrointestinal tract. It is subject to first-pass metabolism in the liver and possibly in the gut wall; the main metabolite is an inactive sulfate conjugate. Salbutamol is rapidly excreted in the urine as metabolites and unchanged drug; there is some excretion in the feces. Salbutamol dose not appear to be metabolized in the lungs, therefore its ultimate metabolism and excretion after inhalation depends upon the delivery method used, which determines the proportion of inhaled salbutamol relative to the proportion inadvertently swallowed. It has been suggested that most of an inhaled dose is swallowed and absorbed from the gut. The plasma half-life of salbutamol has been estimated to range from 4-6 hrs.;
|Antiasthmatic & COPD Preparations
|R03CC02 – salbutamol ; Belongs to the class of adrenergics for systemic use, selective beta-2-adrenoreceptor agonists. Used in the treatment of obstructive airway diseases.
|Tab 2 mg x 100’s.