A contact high is a psychological phenomenon that occurs in otherwise sober people and animals who come into contact with someone who is under the influence of drugs. It involves a supposed transfer of the physiological state of intoxication. A glossary of drug users' language from the 1970s describes the term as "a psychogenic 'trip' without taking drugs by being close to somebody while he or she is on drugs. The term is often incorrectly used to describe the high obtained by inhaling the smoke of other marijuana smokers."
In Alexander Shulgin's PiHKAL book under the 2C-I entry, a notable reaction is observed in a participant who takes a placebo, existing in an environment with other people who are under the drug's influence. The participant wrote that he had "absorbed the ambience of the folks who had actually imbibed the material,".
Stanislav Grof, together with his wife Christina, experienced a contact high assisting a person under LSD therapy described in his book When the Impossible Happens: Adventures in Non-Ordinary Reality (2006) in Part 4 about Pecherskaya Lavra (p. 213, in German edition).
- Rocket Science released an album with the same name in 2001.
- The Godz' first album is entitled Contact High With The Gods.
- The Soup Dragons song Contact High, is a track on their album Hydrophonic.
- Scissor Sisters, Allen Stone, and Ike & Tina Turner had B-side songs by the same name.
- Donovan Leitch's song House of Jansch contains the line: "I gave my baby a contact high."
- The Beach Boys song Kokomo features the line, "Give me a tropical contact high."
- The Toby Keith song Weed with Willie (bonus track from the album Shock'n Y'all) contains the line: "...I do not partake, I just let it pass by; with a grin on my face and a great contact high."
- Nerdcore rapper mc chris released "Older Crowd" which contains the line "can't believe it, I smell reefer, we might get a contact high" specifying the other party had been using marijuana.
- The Austrian movie Contact High deals with this phenomenon.
- In an episode of Family Guy, Meg Griffin has smoked cannabis and has been lazing on a couch. Stewie comments, "It's really sad. And a tiny bit funny! Oh my god, I think I'm getting a contact high!" before falling into a similar state as Meg. "Oh, now I'm messed up too."
- In another episode of Family Guy, Stewie says to Brian, "ooh I think I'm getting a context high" after Brian had ingested mushrooms.
- Australian indie rock band Architecture in Helsinki released a single in February, 2011, named "Contact High", which according to frontman Cameron Bird is about "the notion of a contact high through the intoxication of love."
- On Jan. 15, 2014, on the CNN news program Anderson Cooper 360, a reporter doing a segment on tourism after the recent legalization of recreational marijuana in Colorado, after spending some time in a vehicle with rolled up windows, with several individuals smoking pot, acted apparently intoxicated when speaking to Cooper. In explaining her behavior, she stated her belief that she received a "contact high" from the pot smokers. It is unclear whether the reporter is referring to the proper definition of a contact high, or its technically incorrect variant regarding second-hand smoke effects. 
- Wolfram Keup (1971), "The Vocabulary of the Drug User and Alcoholic: A Glossary", Substance Use & Misuse, 6, p. 353
- "Erowid Online Books : "PIHKAL" - #33 2C-I".
- "Contact High". Contacthigh.at. Retrieved 2011-11-30.
- "Architecture in Helsinki world premiere | music news | triple j". Abc.net.au. 2011-02-17. Retrieved 2011-11-30.
- "CNN reporter high during Anderson Cooper marijuana TV segment". Zap2it.com. 2014-01-15. Retrieved 2014-01-15.