What is the highest prescribed dose for adderall (dextroamphetamine and racemic amphetamine) xr in one single dose?

Depends: Some patients need very little Adderall (dextroamphetamine and racemic amphetamine) and some need very large doses. All patients are different. The highest dose for XR can vary tremendously but I have seen it as high as 60 mg XR ie 2 30mg pills at the same time.

Adderall (dextroamphetamine and racemic amphetamine): Depending on age, size & weight, i would not recommend higher than 60 mg. Daily & certainly no higher than 30 mg. At one time.