Salbutamol is a selective β-2 adrenoceptor agonist. It has very little or no action on the β-1 receptors of the heart. At therapeutic doses, salbutamol acts on the β-2 receptors of the bronchial muscle, the end effect being dilation of the bronchial airways through relaxation of bronchial smooth muscle and reduction of airway resistance.
The active component of VENTOLIN HFA is albuterol sulfate, USP, the racemic form of albuterol and a relatively selective beta2-adrenergic bronchodilator. VENTOLIN HFA is indicated for the treatment or prevention of bronchospasm in adult and pediatric patients aged 4 years and older with reversible obstructive airway disease.