The Impact of Psilocybin on Pain in Fibromyalgia Patients

Rationale: Recent evidence shows that Lysergic Acid Diethylamide (LSD), even when administered in low, non-hallucinogenic doses, can produce analgesic effects and improve pain tolerance in a sample of healthy volunteers. Such results complement what was already observed with other serotonergic psychedelics such as psilocybin: survey studies and case series indicate that its use may lead to improvements in chronic pain conditions such as migraines, cluster headaches and phantom limb pain even at low, non-psychedelic doses. These effects have however not yet been investigated and confirmed in clinical populations under controlled experimental conditions.

Fibromyalgia (FM) is a chronic condition characterised by widespread pain, hyperalgesia, anxiety, disturbed sleep patterns, impaired cognitive functioning and comorbid mood disorders. Most suggested therapies are only associated with small improvements in pain ratings and quality of life. Currently, there is no data concerning the effectiveness of serotonergic psychedelics in improving pain ratings in fibromyalgia patients.

Objective: The present study will explore the effects that the administration of a placebo and 2 low psilocybin doses (5 mg or 10 mg) will have on pain perception in a group of fibromyalgia patients.

Study design: The present study uses a double-blind, randomized, placebo-controlled design. All participants will receive a placebo and 2 doses of psilocybin (5 mg or 10 mg) and will undergo the Cold Pressor Test (CPT) and the Pain Pressure Threshold Task (PPT) o test its analgesic effects.