Psilocybin-assisted therapy shows strong potential to help older adults facing depression, loneliness, and end-of-life anxiety, especially where standard antidepressants often fall short or cause side effects. In adult clinical trials, a single guided psilocybin session led to clinical response rates around 70% and remission rates near 55% within weeks, with benefits lasting 6–12 months, including improved mood, social connection, and sense of meaning. While adults over 65 are still underrepresented in trials, the review highlights clear biological mechanisms relevant to aging brains, including serotonin system support and increased neuroplasticity.