Doxofylline 400mg. + Ambroxol HCl 30mg. is a combination medication used to treat respiratory conditions such as asthma, chronic obstructive pulmonary disease (COPD), and bronchitis. Doxofylline is a bronchodilator that works by relaxing the muscles of the airways, making it easier to breathe, while Ambroxol HCl is a mucolytic agent that helps break down and thin mucus in the respiratory tract, making it easier to cough up. This combination provides both bronchodilation and mucus clearance, improving airflow, reducing wheezing, and relieving chest congestion. It is commonly prescribed to manage symptoms of chronic respiratory diseases and help prevent exacerbations.