[Bryan Howser (OP)]

I was curious about the mechanism of action for lithium in bipolar disorder, and if anyone knows why it was tested in the first place? What exactly about this element, led whoever first began testing it, to try it for treatment of this disorder?
Thanks

[RD]

http://en.wikipedia.org/wiki/Lithium_pharmacology#Mechanism_of_action

[Bored chemist]

There aer two theories about how  effect of Li on bipolar disorder was discovered. One is given in the wiki article the other is that it was found, as with many things, by accident.

They were looking for a treatment for gout. Gout is caused by a buildup of a chemical called uric acid in the joints. Uric acid has a relativeley soluble lithium salt so someone though it was worth trying lithium compounds, like the carbonate, as a means to remove the excess uric acid. It didn't work, but they did notice that some of their gout ridden patients became less depreessed.
This theory requires that some poor soul had both bipolar disorder and gout. Hardly impossible, but rather unfortunate for him.

[Bryan Howser (OP)]

Thanks. None of my teachers could give me any history, and it seemed rather odd that a potentially toxic substance would just randomly be used on depressed patients. Your story is at least plausible. The wiki explanation seems as though there is still some speculation.

[Bored chemist]

To be honest, I think the Wiki story is more likely but I think the one I had heard is interesting.