The dose starts out with a Head rush, Leading into a sudden burst of fear and panic, but these only last a moment, then you are overrun with feelings of calmness and a general relaxed state, Here is where your mind begins to wander, you fade in and out and everything becomes hazey and irrelevent to you... You reach an amazing euphoric state and then Your gently rocked to sleep. Ending the Dose with Sleep or the "Death".......
Just my Idea based on some Personal thoughts and some research.
And from the inter workings of my imagination!
Sorry if anythign is spelled wrong or funny, Im on Vico right now and its midnight.. Bit woozily tired..