You need to make sure her meds are gluten free or she won't be gluten-free. She could be having problems with the dairy. IF she has celiac disease then the villi get destroyed & the tips of the villi are the 1st to go ~~~ the tips of the villi is where the digestion & beak down of dairy (lactose) is done. Many celiacs, once they've gone gluten-free, find they can not eat dairy for a while ~~~ some for months & some for a year or even more until those villi heal.
When one 1st goes gluten-free, it can be a rocky road. Ups & downs with the symptoms coming & going or even seemingly getting worse. The body is adjusting & has a lot of adjusting to do. There are lots of subs for dairy. Almond milk, rice milk, etc.... Google on here to find lots of options or post a thread about subs for dairy. She could use a good probiotic. Culturelle makes a good dairy free, gluten-free, capsule. I'm speaking from the US though & since you said your "mum", then I'm guessing you're in Great Britain or Australia so you need to check if the Culturelle is available there & if it's gluten-free.
Also, you mentioned the gluten-free gravy. When ppl go gluten-free, we suggest they eat only whole foods for a minimum of 3 months (meat, fruits & veggies) & that means no processed foods even if they're gluten-free ~~~ they're still processed food with a lot of stuff in them that can upset the system.
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