Deslorelin implants replace Lupron Depot shots. The implants are supposed to be effective from 9 to 18 months, while Lupron Depot shots can be of the 1-month or 4-month variety. On a per-month basis, the Deslorelin implants are much more cost effective, and from what I have seen in my limited use of both, the Deslorelin implants are more effective. You would NOT use both Deslorelin and Lupron, as they work in the same way. However, the use of a melatonin implant would complement either Deslorelin or Lupron, as it works in a different way. If you use a 4-month Lupron Depot shot, you would actually want to renew it every 3-1/2 months, so that there is some overlap as the old one fades and the new one takes a couple of weeks to kick in. From what I have read, the Deslorelin implants really don't reach peak effectiveness for a month or more. However, when we gave our new boy Pop an implant, his enlarged and problematic prostate was back to normal just 5 days later, as were his urinating habits. Less than a month after the Deslorelin implant he's well on his way to regrowing all lost hair, and it's coming in beautifully. If your vet can get the Deslorelin implants, I highly recommend them, both for effectiveness and cost. And it will stress your ferrets less to get one implant every year or so rather than three or four Lupron shots. Jeff In Memory of Trinny, Neo, Pip, and Mr. Parker Caring for Morphy, Baby Girl, Luna, Dozer, Sabrina, Minnie Mouse, Pop, and Possum the Million Dollar Ferret [Posted in FML 6608]