Biotene for dry mouth - Supply and Alternatives?

[LazyLion]

http://www.biotene.com/

So my mom has been using this for her dry mouth symptoms.
She has Rheumatoid Arthritis and hormonal problems (sweating, etc.)
So she has been using this product.
But now it seems it is no longer being imported and is not available.
Does anybody know why?
And does anybody know of any other remedies for dry mouth?

Thanks.