Experts are warning against the unprescribed use of Adderall and stimulant drugs after an autopsy report showed the substances contributed to the death of a University of Tennessee student last month.

Tanner Wray, 20, collapsed during a charity boxing tournament in February. Medical responders tried to revive him, but he was later pronounced dead at UT Medical Center.

READ MORE | UPDATE: UT student died from unprescribed Adderall use, caffeine during match, autopsy says

An autopsy report released this week concluded the combination of unprescribed Adderall and caffeine were a "significant condition contributing to his death."

Brandon Lock at Belew Drug usually dispenses Adderall for people with attention disorders.

"I think I see it in adults sometimes who are having trouble concentrating, remembering things, being able to focus," Lock said.