My theory is that LC will exacerbate any pre-existing health issues you have (well, many of them), so perhaps your seasonal allergy is being amplified by that.
I suspect that people might be on nicotine patches for a good while--don't know about "indefinitely"--until the LC itself resolves itself.
I had the similar, possibly identical, illness back in the 90's, called ME/CFS, and it just mysteriously went away after a couple of years.

I doubt this is a lifetime sentence, despite some unfortunate people here being rather long-term "long-haulers".

So I guess that the thing to do, if on some kind of stimulant to treat symptoms, would be to back off on it periodically to see where your body "really" is at!
You raised a good point, so thank you for that.