Lutalyse is a product first discovered by Upjohn therefore it is more expensive than the generic brand just like people prescriptions.Go to any AI course and you will see the same old video/dvd of how Upjohn managed to market a synthetic gnrh drug.Now I hope I am right with my gnrh and prostaglandin it has been a few years since I have had to refer to the two.I am sure many others will agree or disagree.SLV