Can I claim food for Celiac disease as a medical expense?

[Opus 17]

Yes, but only the portion of the cost that is more than the cost of ordinary food. 

The IRS says:

You can include the cost of special food in medical expenses only if:

1. The food doesn't satisfy normal nutritional needs,

2. The food alleviates or treats an illness, and

3. The need for the food is substantiated by a physician.

The amount you can include in medical expenses is limited to the amount by which the cost of the special food exceeds the cost of a normal diet.