I know some may argue it is not worth the effort (apparently you were able to claim much more in the past), but really, do you want the government to just take your money? Personally, we try to get as much back as we can from taxes, so that means claiming the incremental cost between buying a gluten free item vs. the non-gluten free item.
The Canada Revenue Agency lays out the gluten free products expense their website. There is a table to show you how to do the calculation, what you can and can't claim, and what you need to submit the expense, such as a Doctors note.
Essential you take the difference in price between the gluten free item and the standard price (incremental cost) and multiply it by the number of purchases you made.
For example, gluten free bread may cost you $5, and whole wheat bread is $1.50. The difference between the prices (the incremental cost) is $3.50. If you bought 10 loafs over the year, you multiple the 3.50 by 10 which ends up to be $35.50. That $35.50 would go towards your medical expense.
I am no accountant, and I can't even begin to explain how the government takes into account medical expenses, but it should help a little bit.
I created a spreadsheet to help us with the calculations. It helped out a lot and made things a bit easier. I recommend it too. The example calculation on the Canada Revenue Agency website should help you quite a lot in setting up a spreadsheet.
So what's this mean to you? If you haven't already, start keeping all your receipts when you purchase a gluten free product. I like to highlight the product and note it on the receipt so I know what it was. I usually don't record anything in the spreadsheet until the years end.
How do you know what the standard cost of an item is? I wish I could tell you, but I can't, because I don't know. I tried to find something on the Canada Revenue Agency website, but didn't find anything, so I just looked at prices at the grocery store and used those prices.
Sounds frustrating and confusing doesn't it? Well, I wouldn't expect anything less from taxes.