Rinsing the mouth (chewing the liquid) and gargling every few hours with Epsom salt and water helps relieve painful sore throat caused by Covid or other respiratory infections. Also swallowing a bit as well.
Epsom salt foot baths really work for sore throats. Soak your feet in a tub of water with about a cup of epsom salts, hot as you can stand for about 20 mins. Then dry your feet and put on two pairs of socks, woollen socks if you have them over a pair of thin cotton socks and go to bed. Each time I've done this my sore throat is gone by morning. Persistent sore throats can return though, so it's good to do the cayenne pepper gargle/ACV cayenne tea during the day if it comes back, and the espsom salt footbath at night before bed.
I poured Epsom Salts into a nice hot bath to soak the aches away. Soaked a hand towel in the tub with me, then laid back with it laid over my face and neck, with another one behind my neck. When I got out of the tub, not only did my achy muscles feel better, but my throat was no longer hurting at all.