Oh yeah.
• 1st Plateau: 1.5-2.5 mg/kg This is the weakest level. This feels slightly intoxicating, a little light headed. Some music euphoria is noticable
• 2nd Plateau: 2.5-7.5 mg/kg This level is often compared to being stoned and drunk at the sametime. When this might seem true, there is also a noticably strong "mental" high also. You can have trouble talking with slurring, and can have a hard time carrying on an indepth conversation, because your short-term memory can be temporarily impared. And occasionally you can have mild hallucinations.
• 3rd Plateau: 7.5-15 mg/kg This level has strong intoxications and hallucinations. Things can become very confusing as your thinking processes are disturbed. You can sometimes daze-off into your own world, and get lost in your own mind. Trips in this plateau can sometimes be unpleasant.
• 4th Plateau: +15 mg/kg This is the strongest level. This is a sub-anesthetic dose, and can be compared to a high dose of Ketamine. Your mind and body become seperated at this level and it can become dangerous psychologically, and physically. Personally I say that you should never have to go this high, it can be very dangerous. But whatever you do, NEVER go past 20 mg/kg (about 2000mg for a 220lb person), this can become very toxic and kill you.