Pilot study of psilocybin in patients with post-treatment lyme disease: A Quick Guide

A small new study is exploring whether psilocybin-assisted treatment may be feasible for people with post-treatment Lyme disease (PTLD), a condition involving ongoing symptoms after antibiotic treatment for Lyme disease.

PTLD can include fatigue, pain, cognitive difficulties, mood changes, and reduced quality of life. While antibiotics effectively treat most Lyme disease cases, the study authors estimate that 10% to 20% of patients develop PTLD. There are currently no established treatments for the condition.

Published February 25, 2026, in *Scientific Reports*, the pilot study included 20 adults with well-characterized PTLD. Participants included 11 women and 9 men, with a mean age of 44. Their median illness duration was 5.7 years.

The eight-week program involved two psilocybin sessions with psychological support. Participants received 15 mg of psilocybin in week 4, followed by either 15 mg or 25 mg in week 6. Psilocybin is a psychedelic that acts on serotonin 2A receptors. Previous clinical trials have suggested potential antidepressant and anti-anxiety effects, while animal research has provided preliminary evidence of anti-inflammatory effects.

This was an open-label, single-arm study, meaning every participant received the intervention and there was no placebo or comparison group.

One month after the second session, researchers reported significant improvements in PTLD symptom burden and quality of life. Improvements were also reported through the six-month follow-up. At six months, general PTLD symptom burden, measured with the GSQ-30, was 40% lower than at the start of the study. Mental and physical quality-of-life scores each increased by 13%.

Measures of mood, fatigue, sleep quality, and pain also showed statistically significant, sustained improvement through six months.

No serious adverse events related to the intervention were reported. However, temporary side effects were common. These included transient high blood pressure in 90% of participants, headache in 65%, rapid heart rate in 35%, pain in 20%, and fatigue in 15%.

The results are encouraging, but they are still preliminary. With only 20 participants and no comparison group, this study does not establish psilocybin as a treatment for PTLD. The authors say further research is needed.

Importantly, treatment in this study took place in structured sessions with psychological support, not as a self-directed approach. This information is for education only and is not medical advice. People with persistent symptoms after Lyme disease should speak with a qualified healthcare professional about their treatment options.