You are literally repeating an urban legend here and now you’re doubling down.

If you actually care about information then here is a layman’s article form the first page of my Google results:

https://action-rehab.com/does-lsd-stay-in-your-spine/

How LSD is Metabolised by the Body

LSD is usually taken orally in the form of a blot on paper or, less commonly, a pill, a watery solution or a gelatine square known as a pane. It passes into the bloodstream and then into the brain and other organs, where it has its characteristic effects. LSD metabolism – the processing of the drug – is largely done by the liver, which breaks it down into different chemicals.

Because LSD is so strong it is only taken in tiny doses – typically between 65 and 200 micrograms (µg), although doses can be lighter or heavier than that. A microgram is one-millionth of a gram.

This can make it difficult to detect and can only be detected in urine using specialist tests. Most routine urine tests will not pick up LSD but there are some special techniques such as liquid-liquid extraction and ultra-high-performance liquid chromatography-tandem mass spectroscopy (UHPLC-MS/MS) that can.

LSD can be detected in blood but only for a limited time. In one study, researchers were able to detect LSD for up to 16 hours in people who had taken 200 micrograms of the drug. In people who had a lower dose of 100 micrograms, they could only detect it for up to 8 hours. LSD may also be detectable in hair for longer, but this does not mean that it is active in your system as markers stay present as your hair grows. This can be useful for drug tests for some substances but again, as LSD is taken in very small amounts, hair tests can be unreliable for its detection.

Does Acid Stay in Your Spine?

So does LSD stay in the spine and body? There is no scientific evidence that it does. While the tiny amounts involved in a regular dose of LSD make it difficult to detect, the best indications are that acid only stays in the system for a number of hours rather than days, weeks or even years.

The belief probably comes from the long-held idea of ‘flashbacks’, which are themselves difficult to prove or quantify. It is not generally accepted by scientists that flashbacks – if they do exist – are a result of drugs being stored in the spinal column or elsewhere in the body.

Potential Long-Term Effects of LSD in Your System

While the storage of LSD in the spine or elsewhere in the system appears to be a myth, there may be other long-term effects of LSD use. These tend to be more psychological than physical. One study found that a single dose of LSD in healthy volunteers was “subjectively considered a personally meaningful experience that had long-lasting subjective positive effects”.

For others, however, the effects can be negative and very serious. Hallucinogen Persisting Perception Disorder (HPPD), is a condition involving perceptual changes lasting weeks or months following the use of a drug like LSD. Using acid and other hallucinogens can be detrimental to mental health, potentially triggering a mental health episode or exacerbating an existing condition

Pretty sure your buddies are idiots who failed to treat LSD with the respect it deserves and ended up psychologically injured by it. That is not science, that is dumdums.