1100-1300mg Dextromethorphan HBr will do the trick.
Seriously though, try getting some more rest. Sleep usually cures most ailments I ever face.
If you do decide to give Buckley's Mixture a chance (as stated above) watch your dosage on that. Don't take 1mg over the recommended dosage (which I believe is 120mg/day) as that stuff contains Ammonium Sulfite which will suffice to a nasty hospital visit if you take any more than the reccomended dosage.
Good luck and feel better!
