Subjects with a change in FEV1 ( delta FEV1 ) greater than or equal to 10 percent decrease after the initial AP dose were restudied on three separate occasions ( greater than 24 hours apart ) after premedication with two puffs of salbutamol ( 200 micrograms ) , ipratropium bromide ( 40 micrograms ) , or sodium cromoglycate ( 2 mg ) , in random order .
