I can't answer that right now. I've used this product for a month and just received another bottle. I've noticed a "little" improvement. He just turned 11 and also he's on GLYCOFLEX stage 3 by my vet. He is also on Nutro Ultra Senior which is top of the line dog food ( I'm a retired dog trainer and also learned what to look for In a dog food). He is still favoring he's right hind leg. I'm giving him another try on Restorapet since the reviews were great and I did research on this product. I also ordered ProPower by Dr. Marty but he hates it so far. He received this injury by my grandsons 2 year lab/pit playing too ruff. She's a very good dog but in her teenage years. She went up under his hind legs - hince the injury.Update!!! 08/5/20. WOW about sums it up! Should have rated this the Last of June..Ruger a Jack Russell mix was having bad right leg problems. It took about 3 months to work. The appt. With my vet the first of May -- he said Ruger's leg was going the way his left leg had been that I might be looking at another surgery.. I told him I was going to give Ruger about another month on Restoapet. It did take a little longer to notice a big difference but I did notice an improvement within 2 1/2 months. I started this in March. The middle of June much better. By July BIG change. He's walking on all fours, no limp. He's jumping on the couch and on my bed no problem. I got my Ruger back. I'm still not letting him jump on my bed if I get there first because of his age. He's 11 years old. BUT I HAVE MY RUGER BACK. He's more alert, running in the yard. I CAN'T THANK YOU ENOUGH FOR RESTORAPET. I know I've written a novel here but I'm still excited about this product. This is on my list to purchase every month. RUGER SAYS THANK YOU TOO!!!!!I ORDERED 1(1)) ORDER OF RESTORAPET AND (1) ORDER OF MELATONIN!!! I RECEIVED (2) BOTTLES OF RESTORAPET AND NO (0) BOTTLE OF MELATONIN!!!! PLEASE MAIL ME MY MELATONIN!!! THANK YOU.