<<Disclaimer: Verify this information before applying it to your situation.>>

There is a wonderful web page, with loads of information, and links to many
other sites concerning celiac disease.  It is at
   http://www.hooked.net/users/sadams
There is a discussion of tax deductions there, with detailed information on
the IRS regulations.  Wether or not it will benefit an individual to use the
deduction may depend on willingness to keep detailed records and how much you
actually spend on gluten free products. Hope this helps.