Yes, I have done nicotine patches twice. The first time it worked like a charm! I haven't felt that good for ~18 months! I was so impressed that I recommended it to a few people I knew who were suffering with COVID long haul, and all of them also had positive results. (Walgreen's 7 mg circular patch w/Light Brown backing)

Then, ~3-4 months later, my cough/throat flem started to come back, just a little. I remembered reading online that sometimes it took two cycles of 7 days of patches, and hunt season was coming... so, I decided to do another round just to be safe. I started with the Walgreen's patches, but I ran out after the first day. When I got to my local Walgreen's store, they were also out of all 7 mg patches.

So, I went down the street to Walmart, where they had Equate Transparent patches (oddly, nothing else in 7mg patches). I bought those, went out side, put one on my arm and drove off. ~55 min later, I was deathly ill. I spent that evening in the ER. They coded my bill "Toxic Effect of Tabacco/Nicotine".

I do not know if there is a difference between the type/manufacture of patches? But, I had two VERY different experiences. I do not know why ¯\_(ツ)_/¯