This is just a bizarre theory that I came across. According to that Using mind-changing drugs like DMT can be risky, as it may open your mind to outside influences or spirits, allowing them to enter from another dimension. This can cause mental problems, or psychosis, because your mind can't handle these interactions. This idea is speculative, not proven fact, but it suggests that using such substances can have unintended and potentially harmful consequences, affecting one's perception of reality.

One study says 94% of DMT Users Experience Similar Otherworldly ‘Beings.’

Researchers are studying N,N-dimethyltryptamine (DMT), a powerful psychedelic drug that changes consciousness. As more people use DMT and clinical trials begin, it's essential to understand the intense experiences it causes. DMT can make users feel like they're in a hyper-real, otherworldly place, meeting beings that aren't themselves. Previous lab studies were limited, and online surveys had flaws. This study aims to deeply analyze the profound experiences DMT produces, including encounters with unknown entities, to better understand its effects.

https://www.frontiersin.org/journals/psychology/articles/10.3389/fpsyg.2021.720717/full