Psilocybin for the Treatment of Cluster Headache

Inclusion Criteria:

- Chronic cluster headache with at least one attack daily

- Episodic cluster headache with periods that are predictable and have a duration of
approximately 2 months

- Attacks are managed by means involving no more than twice weekly triptan use (e.g.,
high-flow oxygen, heat/cold pack)

Exclusion Criteria:

- Axis I psychotic disorder (e.g. schizophrenia, bipolar I, depression with psychosis)

- Axis I psychotic disorder in first degree relative

- Unstable medical condition, severe renal, cardiac or hepatic disease, pacemaker, or
serious central nervous system pathology

- Pregnant, breastfeeding, lack of adequate birth control

- History of intolerance to psilocybin, lysergic acid diethylamide (LSD), or related
compounds

- Drug or alcohol abuse within the past 3 months (excluding tobacco)

- Urine toxicology positive to drugs of abuse

- Use of vasoconstrictive medications (i.e. sumatriptan, pseudoephedrine, midodrine)
within five half-lives of test days

- Use of serotonergic antiemetics (i.e. ondansetron) in the past 2 weeks

- Use of antidepressant medications (i.e. amitriptyline, isocarboxazid, fluoxetine,
citalopram) in the past 6 weeks

- Use of steroids or certain other immunomodulatory agents (i.e. azathioprine) in the
past 2 weeks