Pharmacology Mechanism of action of theophylline in bronchial asthma is: A Phosphodiesterase 4 inhibition B Beta2 agonism C Anticholinergic action D Inhibition of mucociliary clearance 💡 Explanation Mechanism of action of theophylline in bronchial asthma is: ✓ Correct Answer: A. Phosphodiesterase 4 inhibition