I have never done any sort of drugs in the past, nor shall I in the future. However, upon researching the "psychedelic experience" on Wikipedia (I have waaaaayyy too much free time), it seems that a lot of the experiences resemble both symptoms of dp/dr, as well as psychosis. Since chronic dp/dr is often an indication of schizophrenia (which induces psychoses), as the former is the disintegration of one's perception of self and the latter is the disintegration of self, I shall use this page to refer to both categories of symptoms in relation to the question.
The brain contains a powerful hallucinogenic in the pineal gland, called DMT, which is used to cause dreams as well as other phenomenon (research indicates that it may be released in response to trauma). Additionally, psychedelic substances do not act on their own, creating the experiences that follow intake. Rather, they affect the action of normal brain neurotransmitters, such as serotonin and dopamine, often through agonistic actions against certain receptors. Thus, it causes the chemicals that would normally bind to these receptors to build up in other parts of the brain, affecting receptors there that are either similar in structure, or are the same receptor but placed for a drastically different purpose. It is this agonistic action (seen best in experiments involving large doses of LSD) that leads to the perceptional distortions, hallucinations, ego destruction, and the complete splitting of the self from self and reality.
Do take this opportunity to note (et nota bene) that these are the more powerful symptoms of schizophrenia; indeed, the term "schizophrenia" means "split mind" (stemming from the Greek roots schizo meanin split, and phrene meaning mind), not because of a "split personality," as commonly misconstrued, but because of the breakdown of communication between different parts of the brain. This, in turn, leads to a disintegration of the "self." Therefore, it is highly possible that, in those with the genetic factors, there is a protein(s) that cause similar effects as psychedelic drugs, and in those without the genetic factors, the perchance variant actions of stressors in the brain causes miscommunication, hence the "brief reactive psychosis."
Now, you may be wondering what this has to do with dp/dr. Dp/dr seems to be a much milder form of this very action; indeed common dp/dr symptoms are listed among the aspects of the first and second levels of psychedelic experience. It is quite possible that the same perchance variant stressors are the culprit behind the trauma or stress induced dp/dr cases. In drug-induced cases, well, the conclusion is much more transparent.
I do not wish to alarm anyone with dp/dr on this site, but dp/dr can (though is not common) be a symptom of a mild psychosis. This is because of the similar actions of dp/dr and psychoses, as well as the fact that a psychosis is a temporary (sometimes permanent) loss of self, while dp/dr is the perception of that loss. Thus, the latter can be the homeostatic reaction to the other, but still contained within the blanket terms in regards to symptomatic analysis.
In conclusion, the similarities of the neurochemical reactions between dp/dr, schizophrenia/psychosis, and psychedelic drugs (they are also called psychotomimetic for a reason), leads me to the inference that a similar, connecting principle behind the actions of these three psychological factors, and that dp/dr and schizophrenia may be non-drug induced (although they are drug-induced in some cases...) psychedelic states. However, the term "psychedelic" should by no means by confused with the intent and behavior of individuals who take psychedelic drugs recreationally. Nor do intend to reduce the suffering of those with dp/dr and/or schizophrenia to mere chemistry. It is obvious, for those of us whose symptoms are not drug-induced, that dp/dr and schizophrenia are powerful agony perpetuating mental states induced by trauma and/or stress. The purpose of this article was to alert sufferers to this neurochemical similarity, whether it is coincidence or not. It is also my hope that more research will be conducted in this area to prove or disprove my tentative hypothesis.
P.S. Does anyone know what I'm talking about? Or am I just being stupid and pretentious?