Anybody knows if psychedelic dosage is weight-dependent? In research I mostly see dosages per kg, while responsible use wikis list absolute dosages (which matc

Anybody knows if psychedelic dosage is weight-dependent? In research I mostly see dosages per kg, while responsible use wikis list absolute dosages (which matches my experience of user-weight not changing much of the perceived strength). This seems natural to me since the brain does not grow with your weight and psychedelics unlike THC are not liposoluble AFAIK, but this is just me speculating and I have zero pharmaceutical-related education. If it is weight-dependent what mechanism affects the strength?