Is this a recent thing or been this way for a while? What are the possible causes? Recreational drugs? Sleeping over 8 hours a night?, too much sleep can make one dopey. Lack of good quality and/or quantity of sleep? Too many hours of video gaming? Too much TV? other possiblities?
You should try to determine the cause and correct it and chemically you could try Vinpocetine, , Sulbutamine, Chocamine, or Caffeine added or more. If you go the chemical route, try these one at a time at varying doses to gauge it's effect before adding something else.