How can u prevent adderall (dextroamphetamine and racemic amphetamine) extended release from crashing frequently?

Ask your Doctor: It's hard to know exactly what you mean, but as far as "rebound" symptoms, if you will; like as stimulant medications wear off; a common strategy is to have a low dose of immediate release about 45 minutes before the extended release wears off. In the case of adderall, (dextroamphetamine and racemic amphetamine) one could try 5 mgs of dexadrine. Do not make any changes without your doctor's approval.

several options: Get a dose, and a dosing schedule better suited to you. Take an afternoon dose. Use a combination of meds. Use a different med. There is an answer. Work with your dr (hopefully an expert in these meds) to get the effect you need, without the crash.