Asthma (Bio)

Asthma

An inflammatory disease of the lung airways characterized by reversible airflow obstruction and bronchospasm, often triggered by inhaling allergens.

Factors Contributing To Asthma

Includes environmental factors, allergens, occupational exposures, air pollutants, infections, pharmacological factors, exercise, emotional stress, and genetic predisposition.

Clinical Features of Asthma

Symptoms include coughing, wheezing, shortness of breath, and chest tightness. Diagnostic tests may involve family history, physical exams, spirometry, and allergy tests.

Pathophysiology of Asthma

Involves airway inflammation leading to temporary airway narrowing due to pulmonary inflammation, bronchospasm, increased mucus secretion, and cholinergic nerve over-activity.

Agents used in Asthma

Include bronchodilators (B2 adrenergic agonists, muscarinic antagonists, xanthines) and anti-inflammatory drugs (glucocorticoids, leukotriene modifiers).

B2 Agonists

Medications that bind to Beta 2 Adrenoreceptors causing bronchodilation by increasing cAMP levels, examples include short-acting (e.g., Salbutamol) and long-acting (e.g., Salmeterol) compounds.

Muscarinic Antagonists

Drugs like Ipratropium that inhibit acetylcholine action at muscarinic receptors, leading to bronchodilation and reduced mucus secretion.

Xanthines

Drugs like Theophylline that relax bronchial smooth muscle by inhibiting phosphodiesterase, increasing cAMP levels, and have anti-inflammatory effects.

Corticosteroids in Asthma

Inhibit inflammation by regulating gene transcription, examples include inhaled (e.g., Beclomethasone) and oral (e.g., Prednisolone) forms with systemic side effects.

Anti-Leukotrienes

Oral drugs beneficial in asthma, especially in exercise-induced bronchoconstriction, with a low side effect profile and not for acute asthma attacks.