Post-infectious persistent cough may be caused by an underlying inflammation in the airways. Due to its antiinflammatory properties, inhaled corticosteroids (ICS) may be a rational therapeutic approach to reduce cough symptoms. In this randomized, double-blind study, the efficacy of treatment with inhaled extra-fine HFA beclomethasone diproprionate (HFA-BDP) was compared with placebo in patients with post-infectious persistent cough. A total of 72 patients with persistent cough lasting at least 3 days (max. 14 days) following an acute respiratory tract infection were randomized to treatment with extra-fine HFA-BDP (400 microg twice daily for 7 days followed by 200 microg twice daily for 4 days) or placebo. The efficacy was measured by tussometry. The primary endpoint was defined as a reduction of frequency of cough epochs/h at the end of treatment (Day 11) in relation to the baseline level and in comparison to placebo, calculated as the area under the curve (AUC). The treatment with extra-fine HFA-BDP resulted in a greater reduction of cough frequency in patients with post-infectious persistent cough in comparison to placebo. The AUC from Day 1 to Day 11 for the frequency of cough epochs/h between 7:00 am and 11:00 pm was calculated as 605.8 for HFA-BDP and 847.9 for placebo, respectively (P<0.05). There is evidence that extra-fine HFA-BDP leads to a more rapid reduction of cough frequency at the beginning of treatment. A short-term treatment with extra-fine HFA-BDP could be an effective and well tolerated therapeutic option in the treatment of post-infectious persistent cough.