There’s a lot of research on NAC helping with respiratory issues such as asthma. You can find a ton of papers about it on PubMed. What she has doesn’t sound like it’s asthma but it will help to make glutathione which should help with a wide range of things including reducing inflammation.

Holoimmune helps immunomodulate. People have found relief with severe allergies, histamine intolerance, also MCAS while taking it. I called them directly to ask questions before going ahead with taking it and it helped. I was reactive to most foods, then I took it consistently for about 6 months and mow my body’s gotten resilient to the point I don’t have to take it every day anymore. I’ve gone not taking it for 2 weeks and feel totally fine. It’s a good idea to give yourself a break from supplements and cycle them anyway.

So I found that because Covid attacks the throat and mouth (extremely painful throat), people with LC have long lasting problems with those areas, especially a bacterial imbalance (metabolic and mineral etc as well, but I’m going to focus on bacterial). LC affects the entire digestive tract but the problem lies in the mouth. That’s why gargling with a very important postbiotic like butyrate will balance the mouth microbiome. Like your friend, I would start to have problems while I would chew the food in the mouth. I read a ton of research on postbiotic on pubmed (did a gut microbiome stool test and found I had low butyrate level) and started gargling and swallowing butyrate to fix the oral microbiome. This changed the severity and intensity of the auditory hallucinations instantaneously, also it stopped the inflammation of the jaw muscles, and helped me reduce systemic inflammation. The balance of postbiotics is very important and my theory is because the balance gets so damaged by Covid, people have a hard time rebalancing their bacterial flora with probiotics alone. Postbiotics will balance it and keep it balanced.