Oxydex Syrup belongs to the class of medicines called ‘expectorants’ primarily used to treat Asthma and Chronic obstructive pulmonary disease (COPD). Asthma is a chronic breathing problem that affects the airways in the lungs. These airways, also known as bronchial tubes, allow air to move in and out of the lungs. Chronic obstructive pulmonary disease (COPD) is a chronic lung disorder in which there is difficulty emptying the air of the lungs (airflow obstruction). Due to this obstruction, patients experience difficulty in breathing.