Very few celiacs are likely to have any reaction to topical gluten contact. In order for a gut reaction to occur, it is likely that direct contact with the gut lumen is required. Many people with celiac disease have everyday contact with gluten (for instance, bakers with celiac disease who have contact everyday with wheat flour), and do not have any reaction to it. However, there are, on rare occasion, people who have had an anaphylactoid response to gluten, and these people should avoid gluten in all forms. Also, topical gluten breathed into the upper airways may cause symptoms of allergic rhetinitis in rare instances. If there is a simple alternative to a shampoo, cosmetic, etc., you may want to use the non gluten containing product.