Gluten in shampoo?

I think some beauty/cleaning products do contain gluten, like oats, barley etc, but as far as I know, it is not an issue for Coeliac folks since it’s a disease that affects how gluten is absorbed in the intestines, not an intolerance. However, for gluten sensitive or allergic folks, might be worth checking with their GI re: whether they will be affected by gluten contained external use products, they can even do a patch allergy test to determine that.

(Not an expert obviously, just speaking from personal experience and research)

Thanks to the Courtesy of :

https://www.reddit.com/r/glutenfree/comments/dlvgpj/gluten_in_shampoo/