How to fight the come down from stimulants

[bio2016]

Ritalin i take on the regular basis,it does make me very active ,very concentrated,i get 50% more job done, then if i wouldnt take it ,however i have this excity or strong feeling of come down ,makes me a little paranoid ,aunxious....kind of this feeling when i look at the clock and ask myself WHEN WILL IT GO AWAY ?....
some kind of mild depression ....i dont know very very very nasty feeling i hate it but cannot give up my Ritalin ..

Any sugestions on this situation ?