Aieeee. Don't guess! Instrumentation! Tests. Verification. My labs showed a high normal magnesium test so now treating alternate days.
But medical voodoo is far too similar to RV tech voodoo. Rote. Book educated. Little if any hands-on or field experience. This leads to errors. In Rx throw medications at the problem. In RV, change stuff until one or the other happens: The problem gets fixed. The rig gets sold.
Diagnostics is key. This separates the wanna-be's from the truly talented*. As an example when a "Hamster" makes a diagnostic comment on this board I read and digest it carefully. Same exact attention given to novices who document devices and symptoms then take the time to fully list them.
*I don't do A/C, heaters, absorbsion refrigerators, suspension, brakes, roof materials, hitches, or quickeeslipee electric steps, except for comments. Oh I also don't do windows or floors.