Can you get a secondhand high?
If you’ve ever been exposed to it, you may have wondered if you can get high from secondhand smoke. The answer is no, you probably don’t get high from someone else’s smoke.
The common phrase “contact high” implies that if you breathe in secondhand smoke from cannabis, you may feel a buzz (e.g., your thinking may become fuzzy or you may become sleepy). According to some studies, in circumstances when lots of cannabis smoke is blown straight into someone’s face, they may feel a secondhand high, and cannabis may be detected in a urine drug test. However, this occurrence isn’t normal.
Research studies show that when a cannabis smoker exhales, they breathe a very small amount of tetrahydrocannabinol (THC) back in the air. The amount of THC is so little that even if you’re in a room for an hour with people smoking about four joints (cannabis cigarettes), you may not get a secondhand high.
In order to get a secondhand high, you would need to confine yourself in a room with secondhand smoke from at least 16 joints.
One study found that people in an enclosed space with others smoking high-THC-content joints developed a mild contact high and experienced a mild impairment in their motor skills.