Margaret -
You probably should not be feeding those to your dogs because they are not made for dogs. Admittedly, I tried that avenue once because it was cheaper than the "made for dogs" chondroiten and glucosamine that's recommended for larger dogs. It didn't produce any positive effects after one entire bottle so then, we tried arthritus meds. My american bull was experiencing a slight limp. The meds didn't do anything!
Finally, I tried Phycox chews. They are made for dogs and have taken away his limp entirely and he runs and plays like he used to. He's 6 years old. To start, you feed 2 chews in the am and 2 in the pm for one entire container. Then, taper to one chew in the am and one in the evening. He loves them and he's been normal ever since. They can get pricey, but it's worth the health for your dog.
The osteo bi-flex can't be digested properly, it doesn't have the amount of vits they need, and it's just a waste of money. Use them for yourself and try they phycox. We've been using it for 2 years now.
oops!
Forgot the link.
Here you go:
http://www.phycox.com/english/for-dogs.html
It's OK to give "human" grade Glucosamine and Chondroitin to dogs. But you seriously need to watch out for any additives in the capsules or tablets. Artificial sweeteners, Xylitol, sugars, or any other additives, and I would say no -don't give them that stuff. Toxic for them.
However, the basic Glucosamine/Chondroitin is EXACTLY the same substance whether for humans or dogs. The difference is -the price. My vet told me that.
You would be looking at 500mg Glucosamine for every 30lbs body weight (approx) and 200mg Chondrotin also for every 30lbs body weight. That would be the max. dose.
My dog (28lbs approx.) had that dose and it really made a definite difference to her. In damp weather she would limp ever so slightly now and again (she once years ago had a broken leg) Within a week of giving her the Glucosamine/Chondroitin, she stopped limping and never ever did so again the rest of her life.
Dr Foster & Smith ... Glycoflex Classic 600 is the best. 300 beef flavored pills for 30.97. I buy this for my senior dogs, 14 an 15 yrs old both large dogs. Great results.