Considering the second hand high: here’s what we know

Call it a contact high, a secondhand high, or catching down smoke, but all these phrases are used in reference to the same situation. You spent some time in a room with people smoking weed and believe you feel a noticeable buzz. After all, people on TV get contact highs all the time—it’s a popular plotline for both movies and shows, and makes for some hilarious outcomes. But, is this possible? Can you get high from secondhand smoke?

Can You Get Second Hand High? – A Legitimate Concern

Most often, the question Can you get high from secondhand smoke?” stems from truly legitimate concerns. Maybe you don’t want to leave your buddy’s house with a buzz because you’re driving. Maybe you can’t chance getting caught with THC on a drug screen. So, getting the facts about contact highs from second-hand cannabis smoke is really important. The concern is legitimate, and the answer could be yes or no, depending on a few factors.

Behind the Cannabis Contact High – The Science

In 2015, researchers at John Hopkins University put secondhand cannabis smoke to the test in two experiments. In the initial experiment, 12 test subjects were placed in a small room with no ventilation; 6 of the 12 smoked 10 THC-filled joints over the course of an hour. The 6 non-smokers walked away reporting they felt tired, less alert, and not surprisingly, “pleasant.” When tested via drug screening, the non-smoking participants also had THC in both their blood and urine.

The second part of the experiment followed the same setup with the only variant being the room was ventilated. This second situation led to the non-smoking subjects reporting feeling “hungry.” However, there were no positive tests for detectable amounts of THC in either their blood or urine.

Anecdotal stories may be our best source, but..

Anyone who has hung out long enough with someone toking away can tell you that a contact high from secondhand weed smoke is possible. However, simply standing downwind when someone is smoking or catching a whiff of aromatic burning bud may not be enough to make anything happen. The researchers involved with the JHU study pretty much concluded the same by stating:

“Exposure under ventilated conditions resulted in much lower blood cannabinoid levels, and did not produce sedative drug effects, impairments in performance, or positive urine screen results.”

Another important thing to note, roughly half of the cannabinoids including THC are absorbed into the lungs and sometimes more than that. In basic speak, that means the smoke your good pal is blowing out from that Black D.O.G. Pre-Roll beside you is only about half as potent as it was before it was inhaled. If your pal happens to be holding the smoke in for a bit before exhaling, most of the cannabinoids may be depleted.

Can you get high from secondhand smoke? – The Bottom Line

So, with all things considered, a secondhand high is rarer than most people think. You’d likely need to be locked in a small room, no windows, no doors, for a lengthy period of time with a heavy smoker to actually get a contact buzz. Even then, the buzz would likely be short-lived and light. Of course, if you’re trying to stay away from THC for a drug test or any other reason, staying safely distanced is always a good idea. But getting high when you walk through a cloud of cannabis smoke or vape is not all that likely. If you have questions, touch bases with one of our knowledgeable Budtenders at Silver Therapeutics cannabis dispensaries, who are always happy to offer advice.