Story perspectives

Study Finds No Impairment in Cannabis Users After 48 Hours

9/12/2025

Summary

Story summary

A UC San Diego study found no driving impairment in frequent cannabis users after 48 hours of abstinence.
Researchers tested 191 users with a driving simulator, revealing no link between driving performance and THC levels.
Detectable THC in blood does not imply impairment when users are not actively high.
The study questions the justification of laws penalizing drivers with trace THC.
Future research should involve complex driving tasks and larger control groups.

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Story summary

A UC San Diego study found no driving impairment in frequent cannabis users after 48 hours of abstinence.
Researchers tested 191 users with a driving simulator, revealing no link between driving performance and THC levels.
Detectable THC in blood does not imply impairment when users are not actively high.
The study questions the justification of laws penalizing drivers with trace THC.
Future research should involve complex driving tasks and larger control groups.