Pharmacological and Situational Causes
Depersonalization has been described by some as a desirable state, particularly by those that have experienced it under the influence of mood-altering recreational drugs. It is an effect of dissociatives and psychedelics, as well as possible side effect of caffeine, alcohol, cannabis, and minocycline. It is a classic withdrawal symptom from many drugs.
Benzodiazepine dependence, which can occur with long term use of benzodiazepines, can induce chronic depersonalization symptomatology and perceptual disturbances in some people, even in those who are taking a stable daily dosage, and it can also become a protracted feature of the benzodiazepine withdrawal syndrome.
Lieutenant Colonel Dave Grossman, in his book On Killing, suggests that military training artificially creates depersonalization in soldiers, suppressing empathy and making it easier for them to kill other human beings.
Read more about this topic: Depersonalization