It’s commonly thought that LSD stays in the system forever and can cause random flashbacks throughout life — here’s what research says.
When it comes to lysergic acid diethylamide, the psychedelic drug more commonly known as LSD or acid, there’s no shortage of myths.
One urban legend says that LSD causes genetic mutations, while another claims that someone who has taken LSD more than seven times is automatically declared legally insane. In fact, there’s an entire wikipedia page dedicated to myths about the drug.
But what about LSD flashbacks? A common perception around LSD is that the drug stays in the user’s system forever, and that LSD flashbacks and hallucinations can be experienced at random throughout life. Is there any scientific validity behind these claims?
First and foremost, it’s worth noting that we still have a lot to learn about LSD, simply because psychedelic research is extremely limited. Following the hippie revolution of the 1960s, the US Drug Enforcement Administration (DEA) categorized LSD as a Schedule I drug — the most restrictive category — alongside drugs like heroin and marijuana, which has created similar problems for marijuana research.
One study published in PLOS ONE back in 2013 found no link between past-year LSD use and seeing random hallucinations; however, other research suggests that seeing things long after taking the drug is rare, but possible nonetheless.
A 2007 case study found that LSD flashback syndrome was triggered in a man by taking selective serotonin reuptake inhibitors (SSRIs), a popular antidepressant treatment.
Other research describes post-trip hallucinations as less of a “flashback” sensation and more of a continuous disturbance of vision, as Popular Science explains. The condition, called Hallucinogen Persisting Perception Disorder (HPPD), describes a reappearance of the visual phenomena that occurs during an LSD trip that cannot be explained by any other mental disorder or medical condition.
"I think the majority of people could trip relatively safely, but there's a discrete percentage…Maybe one person in 20 will develop serious, continuous problems related to the hallucinogenic experience," Henry David Abraham, the psychiatrist who pioneered the field of HPPD research, tells PopSci. "But that's true for virtually any drug."
Further, even the studies that do go into HPPD tend to only evaluate chronic LSD users, so the jury’s still out on whether someone who tries the drug once may experience persistent visual effects.
In conclusion, there’s no solid research to back the widespread claims that LSD can stay in the system forever and trigger random acid flashbacks throughout life.