Conclusion: Doxycycline has small beneficial effects in patients with acute cough and purulent sputum. These beneficial effects are more prominent, and probably clinically relevant, in patients aged 55 years and over and in patients who cough very frequently and who also feel ill.
Inhaled steroids are the most effective long-term control medicine currently available. They improve symptoms of lung disease and increase lung function. Leukotriene modifiers are long-term control asthma medications that reduce swelling inside the airways and relax smooth muscles around the airways.