A practitioner asks whether nicotine is a safe and useful substance for healing related to Covid-19 (or even other neurological disorders), with perhaps precautions to use in a low dose, like the doctor recommended in a video presentation he watched? What can we tell him?

This physician is seeing astutely that there are nerve-related phenomena dependent on the nicotinic receptors that can be impinged on by the spike protein of Covid-19 virus. To have these receptors occupied by nicotine given exogenously, as with nicotine gum, will have a protective effect and help to moderate symptoms accordingly. It is not at all certain this will be followed up formally with research, but it could be. That would certainly help in devising a more rigorous protocol to achieve the maximum benefit with minimal risks. But this is something not dangerous to do for most individuals on their own, following this doctor's recommendation, and as an adjunct would be better than not doing it at all.