The randomized treatments given once daily at night time as follows: placebo hydrofluoroalkane, 2 puffs (Cipla, Mumbai,India) salmeterol-hydrofluoroalkane, 2 puffs of 25 g (Serevent Evohaler Allen and Hanburys, Middlesex, United Kingdom) fluticasone- salmeterol hydrofluoroalkane, 2 puffs of 250/25 g (Seretide Evohaler, Allen and Hanburys) and fluticasone-hydrofluoroalkane,2 puffs of 250 g (Flixotide Evohaler, Allen and Hanburys).