NIH study found glucosamine alone no better than placebo. It looked
more promising with Glucosamine and chondroitin.
Might want to read this article it gives pros and cons.  
http://www.quackwatch.org/01QuackeryRelatedTopics/DSH/glucosamine.html

AP, I use Osteo Bi-Flex which is a combination of glucosamine and
chondroiton, and have never had any side effects that I could tell.  I have
other medical problems, but don't think the med caused any of them, and it
did help my OA.
Gwen

Take a look at this:

http://www.platinumperformance.com/human/products/productcategories/product.cfm?
category_id=455.

It is more expensive but worked much better for me than the generic
drug store brand.
It has some other things in it as well.  It was recommended by my ortho
who
does not have any connection with the company.  This company is well
known for its research in animal nutrition so they are pretty respected
from what I have been able to find out.

BUT:  what do you mean by uneasiness in her chest?  I would not have
her start
any supplement without talking to her MD first.  The problem is that
there are so many supplements out there that are not monitored by the
FDA.  Each pill can have a different amount in it.

Talk to her MD.

Hope this helps

Tortoise