What the heck is Amantadine?

A-man-ta-dean.
Let me begin explaining this.
It's obviously a prescription pill. I was in a pretty serious car wreck last year in October, and I was prescibed to Amantadine. I was supposed to take one capsule by mouth twice a day.
I have no idea what Amantadine is! I should have done the research a long time ago. I just couldn't find the time. I just now remembered about it.
I found the pill bottle in my bathroom, which it still has some pills in it. I'm not going to flush them yet until I figure out what they heck they did for me!
I guess it might help to know that I have, or had,a TBI. Which stands for Tramautic Brain Injury...
I've been told it's a pill that helps me stay alert to things all the time. I've also heard it's an anti depressant...
I want to honestly know what the heck I was taking for nearly a freaking year!!

What is amantadine?
Amantadine is an antiviral medication. It blocks the actions of viruses in your body.

Amantadine is used to treat and to prevent influenza A (a viral infection).

Amantadine is also used to treat Parkinson's disease and "parkinson-like" symptoms such as stiffness and shaking that may be caused by the use of certain drugs. How amantadine works in these conditions is unknown.

Amantadine may also be used for purposes other than those listed in this medication guide.

http://en.wikipedia.org/wiki/Amantadine

This might help.

In addition to the correct answers of the other posters, Amantadine is also used as to combat fatigue. It has a very low cost, so the insurance companies make the doctors prescribe it instead of the newer/better (more expensive) medications available.