Safety, feasibility, and tolerability of psilocybin in older adults with amnestic MCI: Preliminary data from a SV2a PET imaging study
Alzheimer s & Dementia December 1, 2025 Danielle Bukovsky, Aron Amaev, Jianmeng Song et al.
In a small pilot sample of two older adults with amnestic mild cognitive impairment and three healthy controls, two doses of 25 mg psilocybin given one week apart were safe and well tolerated, with no unexpected or serious adverse events. Expected side effects included dizziness and altered perception, all of which resolved without lasting effects. This double-blind, placebo-controlled randomized study uses PET imaging to measure psilocybin's effect on synaptic density in the hippocampus and prefrontal cortex, and whether changes relate to improved cognition. Preliminary findings support the feasibility of investigating psilocybin in supervised medical settings as a potential treatment for amnestic mild cognitive impairment.