Aside from the main character's visions of monsters and gore, I would have to say this is a thriller. Pretty original plot concept and good acting as well.
The story follows a man who is offered an experimental drug in hopes that he can remember why he was found on the side of the road covered in blood. The movie then leads you into his journey of finding these memories.
Nice twist at the end, though I have a feeling most people will know what that twist is about 10 minutes before it happens, but it doesn't distract from the effect.
Overall it's original, I like the concept, the actors were well suited and nothing really seemed out of place. A couple goofs here and there due to shoddy editing possibly, again, nothing that really distracts from the quality of the story. I rate this a 7/10. I give it 7 instead of 6 because of the lack of recognizable actors and how well the roles were played.