Attention deficit hyperactivity disorder management
There are two major medications derived from methylphenidate's isomers: a racemic mixture of half d-threo-methylphenidate and half l-threo-methylphenidate called methylphenidate (Ritalin, Concerta), and an enantiopure formulation containing just d-threo-methylphenidate called dexmethylphenidate (Focalin).
Dexmethylphenidate
Dexmethylphenidate has a 4–6 hour duration of effect (a long-acting formulation, Focalin XR, which spans 12 hours is also available and has been shown to be as effective as -TMP (threo-methylphenidate) XR (extended release) (Concerta, Ritalin LA), with flexible dosing and good tolerability.) It has also been demonstrated to reduce ADHD symptoms in both children and adults. d-MPH has a similar side-effect profile to MPH and can be administered without regard to food intake.