I’m sorry to hear about the rash. You’re not the only one to have experienced that problem, although yours is worse than others I’ve heard about.
Early last year I started having a rash above the inside right ankle. A touch of cortisone will calm it down for a week or two, but it comes back. I don’t know for sure that this is from the niacin, but two other people I have introduced to niacin have also noted a rash. One had a rash on her chest and back. She stopped niacin for a week, the rash went away, and then she restarted with niacin and the rash still there but tolerable. Another had a rash on her back which went away when she applied some sort of antibiotic cream.
I’ve posed a question about this in the private niacin forum on Telegram. I’ll let you know if others have found a solution.
Thanks for responding - I looked up side effects for the N-Acetyl L-Glutamine amino acid component, and skin rash was a listed side effect. It doesn’t seem like an allergic reaction as I was taking it for over two weeks.
I started back up on a half dose with no rash yet.