I Live In A Small County In MO And There

I live in a small county in MO and there is only 1 doctor for most specialties, such as neurology. He is in his 80's and not useful. From researching on-line I have a lot of problems that fall under Autonomic Nerve Disorder...dizzyness, uncontrollable body temp., low blood pressure, acid reflux, IBS, migraines, etc. I need the name of a specialist in this area. St. Louis would be good, but if none there, anywhere.