Subjects receiving fluoxetine experienced more improvement in percentage of heartburn-free days ( median 35.7 , IQR 21.4-57 .1 ) than those on omeprazole ( median 7.14 , IQR 0-50 , p < 0.001 ) or placebo ( median 7.14 , IQR 0-33 .6 , p < 0.001 ) .