Duolin Inhaler works through two active ingredients. Levosalbutamol helps open narrowed airways quickly, while Ipratropium Bromide blocks certain nerve signals that cause airway tightening. Together, they reduce bronchospasm and improve lung ventilation. This combination inhaler is often used inasthma and COPD management when patients need broader bronchodilator support. Proper inhaler technique is important to ensure maximum effectiveness.