What Was Said
Earlier this year, stories began gaining traction on social media that touted a wild plant, called "opium lettuce," as a safer alternative to prescription painkillers such as oxycodone and fentanyl. One story, on DailyHealthPost.com, had more than 9,000 shares, and another, on Ask a Prepper, had more than 300 comments. Many other sites aggregated the story.
Ingesting or smoking Lactuca virosa stems and leaves can help with migraines, insomnia, anxiety, and more, these sites claimed. But the plant doesn't actually contain opiates and it doesn't pose a risk for dependency or addiction, a point of concern in the United States, where more than 30,000 people overdosed and died with opioids in their systems in 2015 alone.
The Problem With That
Some doctors' manuals from the 19th century do list Lactuca virosa as a pain reliever, but there's little evidence that it works. In one of the only studies of Lactuca virosa for pain, researchers fed mice high doses of a few specific chemicals that the plant produces, then put the mice on hot plates. The lettuce chemicals seemed to deaden the mice to the burning in their feet for about as long as ibuprofen—but that is true of many extracts isolated from plants and put through this hot-plate test, says Elizabeth Williamson, a pharmacist from the University of Reading in the United Kingdom: "If you search this test you will get thousands of hits!" On the plus side, there's also little evidence that Lactuca virosa is harmful, unless, perhaps, you eat a salad's worth of it. It's very bitter.
About as Appealing as Burnt Lettuce
Many doctors are trying to move away from prescribing opioids for chronic pain in response to the addiction and overdose crisis, and there's been little evidence gathered about the health outcomes for people who are on opioids for longer than a year. There's good debate going on about what doctors should use instead. Physical therapy? Plain old Tylenol? Smoked wild lettuce, however, shouldn't make the list.
A version of this story originally appeared in the August/September 2017 issue of Pacific Standard.