I am sorry to hear your girl has arthritis.
Unfortunately as our pets get older Osteoarthritis can develop and we want to keep them as pain free and as comfortable as possible.
Glucosamine and chondroitin are substances both found naturally in animals of which the highest concentration is found in cartilage.
As an animal ages or if there has been damage to cartilage/joints, the production of glucosamine cannot keep up with the bodies need.
This is where supplemental glucosamine can be helpful. Veterinarians have started to use supplements as an aid to pain relief in middle-aged to older dogs that have signs of Osteoarthritis.
Evidence suggests that the use of glucosamine in combination with chondroitin sulphate as part of a treatment protocol may help improve mobility of joints and reduce joint pain.
There are lots of different preparations in both the human and veterinary market and your veterinarian would be able to best advise you on whether your Sheltie would benefit from taking a glucosamine chondroitin supplement and what type to give her.
Some dogs can have side effects as result of taking glucosamine chondroitin such as gastrointestinal signs (vomiting and diarrhoea).
In addition, depending on the degree of osteoarthritis, other kinds of pain relief may be required to make sure she is comfortable.
I would suggest discussing with your vet, who can assess the level of osteoarthritis and then recommend a treatment protocol best suited for her.