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What is All of the following drugs useful in the treatment of a patient with acute bronchial asthma except and explain in detail?
Ans. is 'c' i.e. Montelukast Montelukast (and Zafirlukast) is a Leukotriene receptor antagonist Leukotrienes mediate many of the critical elements of asthma. They are potent bronchoconstrictor. Montelukast (and Zafirlukast) are effective in blocking their action. These drugs provide protection against exercise induced asthma and reduce the frequency of exacerbation, but are of limited usefulness is acute asthma. Drugs used in Acute Asthma are Beta - 2 agonists* Salbutamol (Albuterol) Bitolterol, Pirbuterol, Terbutaline Anticholinergics* Ipratropium bromide Systemic corticosteroids* methylprednisolone, Hydrocortisone I think the option Hydrocortisone needs some extra explanation. Even though glucocorticoids are the first line agents for chronic asthma, they are also used in acute asthma. Harrison writes - "Systemic or oral steroids are most beneficial in acute illness when severe airway obstruction is not resolving or is worsening despite intense optimal bronchodilator therapy." Also Remember Another class of drugs blocking the action of leukotrienes is 5 - lipoxygenase inhibitors* eg. - Zileuton* It prevents the synthesis of leukotrienes by inhibiting 5 - lipoxygenase.