Acute psilocybin and ketanserin effects on cerebral blood flow: 5-HT2AR neuromodulation in healthy humans.
Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism February 26, 2025 Kristian Larsen, Ulrich Lindberg, Brice Ozenne et al. 9 citations
Psilocybin, the active compound in magic mushrooms, reduces blood flow in the brain. In a study of 28 healthy volunteers, psilocybin decreased cerebral blood flow by about 11.6% at peak effect, while the serotonin blocker ketanserin had no significant effect. Psilocybin also constricted the internal carotid artery by 10.5%, whereas ketanserin did not. These findings suggest that psilocybin's effects on brain blood flow involve the serotonin 2A receptor and may help explain its therapeutic potential for conditions like depression.