Psilocybin May Ease Post-Treatment Lyme Disease Symptoms, Small Trial Suggests

Of all illnesses transmitted in the United States by the bite of an insect or arachnid, Lyme disease is the most prevalent.

Almost half a million people are diagnosed and treated for it each year. The disease results from bacteria passed on by an infected tick.

However, antibiotics do not lead to recovery for everyone.

For months, or even years, a considerable number of people continue to experience fatigue, brain fog and bodily pain after treatment.

Another medicine may potentially offer help.

A small pilot study involving 20 people has found that two clinically supervised doses of psilocybin were linked to substantial improvements in post-treatment Lyme disease (PTLD).

Albert Garcia-Romeu and his team at the Johns Hopkins Center for Psychedelic and Consciousness Research led the experiments, with the findings published in Scientific Reports.

Psilocybin and post-treatment Lyme disease symptoms

Two weeks after receiving the second, final psilocybin dose, participants reported that their overall symptom burden had fallen by 52 percent from baseline.

At six months after the final dose, symptoms were still approximately 40 to 50 percent below baseline.

At each follow-up, depressive symptoms stayed 50 to 60 percent lower than baseline. Scores for sleep disturbance remained 40 to 50 percent lower, while fatigue severity stayed 25 to 30 percent lower.

Across the clinical trial, total pain scores declined by around 40 to 50 percent.

"Across all outcomes," the authors write, "within-participant standardized effect sizes were large and remained stable when excluding multivariate outliers."

Although Garcia-Romeu and colleagues describe the results as "sufficiently positive", they stress that they are preliminary and require follow-up in randomised, controlled and blinded trials.

Scientists cannot yet determine whether psilocybin itself caused the improvements in PTLD symptoms.

PTLD is sometimes called ‘Chronic Lyme Disease’. However, the US Centers for Disease Control and Prevention advise against this label because it suggests the bacterial infection is continuing, which has not been established.

"We propose further rigorous investigation of psilocybin and other classic psychedelics as potential avenues for novel, effective treatments for this debilitating condition," the authors conclude, "as well as other infection-associated chronic conditions such as Myalgic Encephalomyelitis/ Chronic Fatigue Syndrome (ME/CFS), Post-acute sequelae of SARS-CoV-2 infection (PASC), and fibromyalgia, that may benefit from similar approaches."

Limited research into psychedelic treatments

Research in this area has so far been limited and fragmented.

In 2025, a US pilot trial examined psilocybin-assisted therapy in five people with fibromyalgia. Relative to baseline, participants reported better pain symptoms, mood, social cognition, sleep and overall functioning.

Meanwhile, another recent case study recounted the experience of a woman whose long COVID reportedly improved after she took hallucinogens with guidance from a therapist. The evidence was unclear, but the idea received widespread interest.

PTLD shares many symptoms with post-viral conditions such as long COVID, in which symptoms following infection can persist for unknown reasons.

There is a lack of accepted treatments, prompting some patients and researchers to explore hallucinogens.

Take, for example, a 2023 case report involving an immunocompetent man who developed Lyme disease as well as babesiosis, another tick-borne illness.

Despite several courses of antibiotics, he continued to experience partial remissions and relapses, with each episode lasting roughly two years.

Over several decades, he experienced fatigue, neck pain, myalgias, night sweats, anxiety, panic attacks, depression, cognitive dysfunction and insomnia.

The patient had another relapse at the age of 70. Medicines for anxiety and depression did not help.

"After suffering for three months," the patient's case report reads, "he began microdosing psilocybin (desiccated whole mushrooms) 100 mg orally three times a week, increasing the dose to 125 mg after two weeks. Within two days, there was a noticeable improvement in mood. Within two weeks he was feeling consistently well again."

When the case report was published, he remained in remission and was still microdosing psilocybin.

Yet this was only a single case study conducted outside a clinical environment. The recent Johns Hopkins pilot trial aims to go further.

How the Johns Hopkins trial was conducted

No approved diagnostic test currently exists for PTLD. Nevertheless, the pilot trial authors say they applied strict criteria when choosing participants for psilocybin-assisted therapy.

Volunteers needed a detailed history showing previous Lyme disease and had to have current symptoms. Conditions capable of producing similar symptoms also had to be excluded.

Following weeks of preparation, participants were given a first psilocybin dose of 15 mg, then 25 mg two weeks afterwards. Two participants stayed on the lower dose for the entire study.

At every session, volunteers’ vital signs were closely monitored. They also reported any new or worsening physical or mental-health events occurring during or after each dose.

No serious adverse health effects were reported, though headaches, nausea and hypertension were frequent but temporary.

Twelve of the original 20 participants also agreed to have their sleep monitored with wearable devices during and after the 8-week trial.

The results indicated a longer-term reduction in total sleep time after psilocybin was administered.

More research is required to establish whether these changes also affected sleep quality or daytime sleepiness. However, excessive sleep is often a problem among people with PTLD.

For now, no firm conclusions can be drawn about psilocybin’s effects on PTLD. The trial did not include a placebo, and patients knew they were receiving psilocybin.

Garcia-Romeu and colleagues say future research will investigate health biomarkers measured before and after psilocybin treatment, alongside firsthand accounts from trial participants.

Research into hallucinogenics for mental health, pain and inflammatory disorders is only beginning, and conducting more robust randomised studies will take time.

"The results of the current trial are preliminary and should be considered with caution," the trial researchers note.

"Yet findings underscore the compelling possibility that psilocybin-assisted treatment may significantly mitigate key symptoms of PTLD across several physical and neuropsychiatric domains, that participant quality of life may improve substantially… and that these benefits can persist well beyond the time course of acute drug effects for some patients."

The study is published in Scientific Reports.

This article was fact-checked by Rachel Garner and edited by Peter Dockrill. While we take pride in our process, we are only human. If you notice an error, please let us know.