Can adderall (dextroamphetamine and racemic amphetamine) cause insomnia in someone who has hypersomnia?

Yes: Adderall (dextroamphetamine and racemic amphetamine) is a potent stimulant used to treat attention deficit disorders, sleep disorders, depression, etc. It can reverse hypersomnia and even cause insomnia.

Insomnia: Adderall (dextroamphetamine and racemic amphetamine) contains a combination of amphetamine and dextroamphetamine. Both these medicines are central nervous system stimulants and might cause insomnia. Talk to your doctor, and also you might if you take it earliest time when you wake up you might minimize this side effect.