I’ve had canker sores all my life but recently, I’ve had them for a longer period (several weeks). Went to see several doctors and they all said that they were canker sores. Take D3, relieve your stress, eat better. Did a lifestyle change and this seemed to have alleviated it to a point but I still have a few. Then it hit me that this could be related to acid reflux (I also have a constant sore throat which is a symptom of acid reflux). Another thing I noticed was a strange sensation in my mouth similar to having excessive acid. I think my stomach is producing extra acid during times of stress and I probably have a leaky stomach valve. I will try and take some Zantac or Prilosec and see if this helps. I’m tired of having canker sores.
I am a firm beleiver that allergies in the mouth are caused by what is put in the mouth, is your little daughter eating sweets with colour or ice lollies etc as years ago my young daughter used to be in a terrible state with blistered skin rashes until we discovered that best site she was allegic to food colour and as an adult she still is ie colour in sweets and icecream etc, worth a try as it is frustrating when a child is in pain, also orange juice is very acidic, interested to know if this helps but perhaps you already had did all this.
I have been away from this site for a while but recall some suggeation of a link between acid indigestion and mouth ulcers. In my opinion there is a definite link (in my case at least). I lost a lot of weight last winter which had the benefit (expected) of putting an end to the acid reflux, and also the extra effect (unexpected) of seeming to clear up the ulcers. At the time I was under a lot of stress, hence the weight loss. I know some folks reckon stress and anxiety actually cause or aggravate their mouth ulcer problem but this was certainly not my experience.
I had a sore throat and burning mouth for months. The doctor said it was acid reflux, but I did not have the usual burning symptoms of that. He prescribed antacids anyway, no good. In the end I found out that I have a gluten I tolerance and it was the gluten that attacked all the membranes. No gluten in,y diet and I am fine, big trouble any time I eat gluten. So go gluten free. I’ve had reoccurring mouth ulcers for about 12 years And I have realized , that was about the same time I was diagnosed with Gerd ! But I never put two and two , together I was put on a medicine for the Gerd , but since I only have one kidney , (with problems) I can’t take the meds prescribed. I’m hoping my dr can find something for my problems Surgery will probably be the next step.