Rash on face.

Hi Guys, 

I've been using MMS for two years now. It's helped with a gum abscess and with diarrhea. I've struggled with figuring out the right dosage though. I use 3 drops of the salt and the acid. Pour in distilled water and then add 3 drops of something I'm told increases efficacy. 

Since last winter I've developed a rash on my right cheek. Initially it was very mild redness but it has no spread and it's very upsetting. I took the drops for a few days but it didnt help. Can someone help with sound advice with what to do. It's not this slightly inflamed redness which tingles. I went to a derm who said it was dermatitis and she prescribed hydrocortisone which I did not use. Any advice with regards to how to treat this will be greatly valued.