Gluten Free Thailand
In summary there is very little understanding of allergies or celiac issues in Bangkok, around Thailand and in fact in SE Asia. Smaller restaurants are not super knowledgeable on what you wish to avoid. Hotel restaurants and the more professional places will have Gluten Free Options.
We have listed a few websites with comprehensive information, Click on the name for the website:
Probably the best website, offers free translation cards or with a small donation.