The aim of this trial is to determine the potential effects and mechanisms of cannabinoid-induced pain relief in complex regional pain syndrome (CRPS). Multiple psychophysical approaches will be conducted in conjunction with psychological and inflammatory marker testing to determine if and how cannabinoids produce stabilized improvement in CRPS-related pain and comorbidities.

The trial consisted of a pre-treatment screening period, six-week treatment period and a two-week follow-up.

Complex Regional Pain Syndrome (CRPS) is a debilitating and perplexing chronic pain condition that produces incalculable suffering to millions of individuals worldwide. The enigmatic nature of CRPS has left it difficult to treat. CRPS is characterized by a constellation of pain, sensory, autonomic, and motor symptoms that is difficult to pinpoint the source of injury/inflammation. Although unclear, a common cause of CRPS are radial fractures that demonstrate aberrant processing 4-6 weeks after injury.

The aim of this trial is to determine the potential effects and mechanisms of cannabinoid-induced pain relief in complex regional pain syndrome (CRPS). Multiple psychophysical approaches will be conducted in conjunction with psychological and inflammatory marker testing to determine if and how cannabinoids produce stabilized improvement in CRPS-related pain and comorbidities.

The trial consisted of a pre-treatment screening period, six-week treatment period and a two-week follow-up.

Inclusion Criteria:

1. Provision of signed and dated informed consent form.
2. Are between 21-75 years old
3. Ability to communicate in English
4. Volunteers with no previous medical history (e.g., cardiac or pulmonary disease)
5. Are not currently using any type of cannabis, including hemp or CBD
6. Currently 30 days cannabis free
7. Participants with ongoing CRPS [Type 1 or Type 2)] for at least 3 months prior to participation (medical record confirmed)
8. Agrees not to use cannabis, including hemp or CBD, outside of the study during participation in the study
9. Agrees not to use opioids or barbiturates during participation in the study

Exclusion Criteria:

1. Fail cannabis screening
2. Active pulmonary disease
3. Allergy or past adverse effects or negative past experiences from cannabis
4. Positive urine drug test for THC, barbiturates, opioids, oxycodone, or methadone prior to study session 1 or session 2
5. Any significant illness, including cardiovascular disease, diabetes, renal and liver disease
6. Any current or history of an immunocompromising disease or condition (such as lupus, psoriasis, multiple sclerosis, etc.)
7. Any current or history of neurologic conditions, including Parkinson disease, dementia, cognitive impairment, history of seizure disorder, and history of traumatic brain injury/head injury
8. Participant meets DSM-V criteria for current major psychiatric illness, such as bipolar disorder, major depression, psychosis, substance use disorder, or schizophrenia
9. Any current or history of suicidal ideation or attempt
10. Patients with clinically significant laboratory abnormalities