PHARMACOLOGY
Pharmacotherapeutic Group: β₂ adrenoreceptor agonist.

 Pharmacodynamic Properties:Salbutamol is a β₂ adrenergic agonist and thus it stimulates β₂ adrenergic receptors. Binding of salbutamol to the β₂ receptors results in the relaxation of the bronchial smooth muscles. Salbutamol also inhibits the release of bronchoconstricting agentsfrom the mast cells, inhibits the microvascular leakage and enhances the muciliary clearance.

 Pharmacokinetic Properties:

Absorption: Readily absorbed from the GIT; Onset: 30min; Duration: 8 hr.

Metabolism: Hepatic and in the gut wall

Excretion: Via the urine as metabolites and unchanged drug. Some excretion in the faeces.

INDICATIONS

Asthma, Bronchitis, Emphysema, Cough, COPD

 DOSAGE & ADMINISTRATION

5-10 ml three times a day.Adult: 2-4mg (upto 8mg) three times daily; Child: 2mg three times daily

 ADVERSE DRUG REACTIONS

Fine skeletal muscle tremor especially hands, tachycardia, palpitation, muscle cramps, headache, paradoxical bronchospasm, angioedema, urticaria, hypotension and collapse.Potentially Fatal: Potentially serious hypokalaemia after large doses.

 PRECAUTIONS

Pregnancy, mild to moderate pre-eclampsia, arrhythmias, hyperthyroidism, hypertension, diabetes mellitus, myocardial insufficiency, susceptibility to QT-interval prolongation. Monitor serum potassium levels. In women treated for premature labor, monitor hydration status, cardiac and respiratory function minimise volume of infusion fluid. Discontinue treatment if patient develops signs of pulmonary oedema.

 DRUG INTERACTIONS

Diuretics, corticosteroids and xanthines may augment hypokalaemia. Cardiovascular effects potentiated by Monoamine-oxidase inhibitors, Tricyclic antidepressants, sympathomimetics. Reduces serum levels of digoxin. Hypokalaemia induced by salbutamol increases the risk of digitalis toxicity. Blood Prerssure should be closely monitored if linezolid is used concurrently with salbutamol.

 CONTRAINDICATIONS

Eclampsia and severe pre-eclampsia, intra-uterine infection, intra-uterine foetal death, antepartum haemorrhage, placenta praevia and cord compression, threatened miscarriage, cardiac disease.

 PRESENTATION

ASMAREX SYRUP: Each bottle contains 100ml of syrup