Frequent cannabis users show no driving impairment after two-day break

Study finds no driving impairment in frequent cannabis users after 48 hours of abstinence.

Why it matters

  • Implications for public health and enforcement of cannabis-related driving laws.
  • Challenges the reliability of blood THC concentrations as indicators of impairment.

By the numbers

  • Study involved 191 cannabis users and a smaller comparison group of non-users.
  • About 15% of Americans currently use cannabis.
  • Most intensive users smoked an average of four joints per day.

The big picture

  • Cannabis usage is widespread and understanding its effects on daily activities like driving is crucial.
  • Unlike alcohol, there is no reliable biological test for cannabis intoxication.

What they're saying

  • Some comments question the relevance and purpose of the study.
  • One comment sarcastically notes that it's unsurprising that a drug with a short duration has no effects after two days of abstinence.

Caveats

  • Study conducted in a controlled lab environment.
  • Did not address all possible driving scenarios.
  • Nonuser comparison group was small.

What’s next

  • Further research needed to explore real-world driving scenarios and larger comparison groups.