Bunase-L 0.5 mg Respule is a combination medication primarily used to prevent or treat symptoms of asthma and chronic obstructive pulmonary disease (COPD), such as shortness of breath, coughing, or wheezing (whistling sound while breathing). Asthma is a chronic (long-term) respiratory condition in which airways narrow, swell, and produce extra mucus, leading to difficulty in breathing.