She should talk to her doctor. she may have heard this in relation to a medication used to treat high uric acid levels in fibromyalgia patients and is said to reduce pain. The name of the drug is allopurinol. Here is an article you can copy and paste about it https://pubmed.ncbi.nlm.nih.gov/34715996/.
Here is a quote about how uric acid affects those with fibro. The overactive neurotransmitters going into the muscles also induce a buildup of lactic and uric acid in the muscles causing trigger points, or areas that have severe sensitivity to touch." https://www.jacksonsun.com/story/news/local/2018/09/13/dealing-pain-fibromyalgia/1291617002/
One of the absolute best things to do for fibro pain may seem counterintuitive but it is exercise. It REALLY helps.
This article has ways to naturally reduce uric acid. https://www.healthline.com/health/how-to-reduce-uric-acid Really simple stuff like drink coffee is on the list. Cutting down on red meat. Avoid sugar. And more specific details. Give it a read.
Good luck to your daughter and let me know what you think.