Whats the difference b/w adderall (dextroamphetamine and racemic amphetamine) xrand d-amphetamine salt combo xr? Does the latter cause more side effects?

All amphetamine. Adderall (dextroamphetamine and racemic amphetamine) is a combination of 4 amphetamines. D-amphetamine is one of the 4. the combination pf adderall (dextroamphetamine and racemic amphetamine) salts refers to a generic form of adderall (dextroamphetamine and racemic amphetamine).
Subtle difference. Drugs and molecules occur in 2 different forms with the same composition called enantiomers and are physical mirror images: dextro (right), levo (left). Racemic is a mixture of both. Because d-amphetamine is generally more active than l-amphetamine in its also amplifies side effects. Amphetamine is racemic amphetamine with d:l ratio of 1:1. The "salts" (Adderall) work out to be a 3:1 ratio.