maybe ive just been lucky del but at 25 pound its worth a try m8 it was about a week or two before i felt a difference but you must have it on even if your only in loft for a second and if like me you keep baskets in your van or car mines is bad if im near wood shaveings and dropings mixed i have to use shreded paper in baskets that helps when training or transporting the birds hope it helps you m8