For the last 4 years I've been experiencing progressively worse fatigue symptoms. Best described as follows:

Hard to speak
Hard to "ignite" movement
Extreme fatigue, but not sleepiness
Full body weakness
No will or motivation
Little to no pleasure in anything
Poor concentration, memory

I've extensively checked into the possibility of it being a sleep disorder or some kind of diabetes, but I came up negative for everything in the tests.

The only thing that can bring me out of my comatose state pretty much instantly is Ritalin (methylphenidate), even as little as 2.5mg.

So does anyone know what disorder this might be? Ritalin gives me really bad anxiety and makes focusing hard among other things, so I'd rather fix the source of the problem rather than treating it.

Thanks for any comments and suggestions