Hi,
Sorry to hear you suffer from Celiac Disease. I did find this information from the Celiac Foundation about federal tax deductions. Note, that you are advised by them to follow the steps below, and I stress that you want a physician's diagnosis and prescription and need to only claim the incremental cost of the GF diet (and keep good records).
Step One: Get an official, written diagnosis from your physician and a prescription for a gluten-free diet. You will need to submit this form with your taxes, so make sure to keep a copy for your records.
Step Two: Save your receipts for your gluten-free groceries.
Step Three: Based on the list above, figure out what you can deduct and then start your calculations! You will need to calculate the difference between gluten-free products and non-gluten-free products from the grocery store.
Please cheer below if this helps and good luck with the management. I know it can be tough.