The most likely risk are not the majority of psychedelics themselves, but the quality of the substance you are getting as well as potency and &quot;therapeutic&quot; window. As they are controlled substances, what you are getting is often synthesised from reagents that are known carcinogenics and poorly purified. In many cases, it is not the real substance but a replacement or a mixture of various other chemicals that is supposed to mimic superficial effects. In addition, some psychoactive substances are active in the ug range and therefore have a high likelihood of leading to severe side effects because of overdosing. Also, the dosage window and thus the difference between hypnotic and anxiogenic&#x2F;severe side effects can be in the range of mgs as well. Therefore one should be cautious if you cannot get access to them in a controlled&#x2F;legal environment and certainly should not try every research chemical or analogue that appears on the internet.