I've had long COVID for a number of years. My symptoms included severe dizziness, absolute exhaustion, foggy brain and a number of more mild symptoms. I've tried numerous holistic products. Adrenal support seemed to help as did increasing my sodium intake. I could walk only about 2-3 yards and then had to rest and catch my breath. The day before Thanksgiving, I went for a walk and had a very hard time breathing. The next morning I put on a quarter of a patch (about 5 mg nicotine) on my shoulder. About 4 hours later I took a walk and I had no trouble breathing. I had energy all day. On Thanksgiving Day I drove over 50 miles, set up a tent, put bedding, etc from my car, into the tent. All in about 40 minutes. Wasn't tired. On Halloween I did the same thing but it took me over 2 hours, because every 10 minutes or so I had to rest. It's 10 days since I had my last patch on. I still feel fantastic. No need to nap during the day, no exhaustion, no dizziness. I don't know how long this will last, but I'm grateful.
I never smoked, by the way. And I've been a vegetarian for over 50 years and a vegan maybe about 5 years.