"High dose studies of rats suggest that psilocin taken orally is distributed througout the body. Concentrations in tissues appear highest about half an hour after ingestion, decreasing rapidly over the next three to four hours. The adrenal glands of the test animals show the highest concentrations after the first hour, until then the kidneys have more. The small intestine, skin, bone marrow, lungs, stomach, and salivary glands also have significant concentrations-- greater, in fact, than those in the brain...
In the high dose study of rats, all but 6 pecent of the psilocybin was excreted within twenty-four hours. In humans, only 80-85% of psilocybin and its metabolites is excerted within 8 hours, in the urine (about 65%), bile and feces (15-20%). Some 15-20% olingers on, stored in fatty tissues; significant quantitites appear in urine up to a week later. A full 25% of the originally administered dose enters urine as psilocin."
