False quinine does nothing to help with Covid 19. It has been proven again and again. In fact studies are now showing it could in fact be dangerous to your health. I will see if I can find all the references and post them for you.
I keep both regular and diet tonic water on hand for relief from restless legs syndrome. I don't know where I learned of this but I have found it works for RLS. I will drink 1/2 cup to one cup at night if my legs start acting up. I had a bottle of it in the fridge for a long time because my legs had not bothered me for many months. But recently it started up so now I have two bottles on hand.
Bev, my husband has idiopathic peripheral neuropathy and sometimes has leg and foot cramps. Drinking diet tonic water helps with that. When that condition is acting up, he has a couple of glasses a day.
Mackie I am glad it helps your DH. I have had RLS for as long as I can remember. I even get it on long vehicle rides. I remember one time on a commuter bus I inadvertently kicked the seat in front of me a couple of times. Back then I knew of nothing that would help me.