Recruiting

Early Phase 1

Inhaled CannabisBrain Mechanisms Supporting Cannabis-induced Pain Relief

Sponsor:

UCLA

Code:

NCT04982965

Conditions

Sciatica

Lumbar Radiculopathy

Lower Back Pain

Degenerative Disc Disease

Chronic Low-back Pain (cLBP)

Eligibility Criteria

Sex: All

Age: 21 - 65

Healthy Volunteers: Accepted

Interventions

Active Cannabis

Placebo Cannabis

Study Details

Brief summary:

Chronic low back pain is a common and disabling condition that affects millions of people in the United States. Many people with chronic low back pain do not get enough relief from current treatments. Cannabis may help reduce pain, but researchers do not fully understand how it affects the brain in people with chronic pain. The purpose of this study is to examine how inhaled cannabis changes brain activity and reduces pain in people with chronic low back pain. Results from this study may help researchers better understand how cannabis works for pain and support the development of improved pain treatments.

Conditions

Sciatica

Lumbar Radiculopathy

Lower Back Pain

Degenerative Disc Disease

Chronic Low-back Pain (cLBP)

Study ID

NCT04982965

Start date

May 7, 2021

Status verified date

Jan, 2026

Completion date

Mar 15, 2027

Anticipated

Primary completion date

Jan 15, 2027

Anticipated

Eligibility Criteria

Sex: All

Age: 21 - 65

Healthy Volunteers: Accepted

Inclusion Criteria:

Between 21-65 years old
Currently 30 days cannabis free
Lower back pain for three months or more
Are not taking opioids
If female and of a child bearing potential age, are not pregnant or nursing mothers
Do not have mental or neurological conditions inhibiting sensory/motor functions
Do not have a lifetime history of dependence on cannabis
Do not have a lifetime history of DSM-IV schizophrenia, bipolar disorder, panic disorder, or psychosis
Prior THC-containing cannabis experience within the past two years
Agrees not to use cannabis outside of the study during participation in the study
Agrees not to use opioids or barbiturates during participation in the study
Agrees not to drive a motor vehicle within 4 hours following last use of inhaled cannabis during participation in the study

Exclusion Criteria:

Active pulmonary disease
Allergy or past adverse effects or negative past experiences from cannabis
Positive urine drug test for THC, barbiturates, opioids, oxycodone, or methadone
Any significant illness, including cardiovascular disease, diabetes, renal and liver disease.
Any current or history of an immunocompromising disease or condition (such as lupus, psoriasis, multiple sclerosis, etc.)
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
Any current major psychiatric illness, such as bipolar disorder, major depression, psychosis, substance use disorder, or schizophrenia
Any current or history of suicidal ideation or attempt
Overt sensitivity to thermal stimulation
Resting blood pressure > 140/90
Resting heart rate > 100 beats/minute
Prisoner
Institutionalized
Claustrophobia
MRI contraindications
Participation in any new (within 2 weeks prior or any time after enrollment) pain management procedures during the study period
Known history of vasovagal fainting, syncope, or severe adverse reactions associated with blood draws or needle procedures

Study Design

Enrollment

100 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Basic Science

Interventions and Outcome Measures

Arms

experimental: Active THC

Participants will be administered 400mg of vaporized cannabis (5.1%) before pain testing and fMRI.

placebo comparator: Placebo THC

Participants will be administered 400mg of vaporized cannabis (<.1%) before pain testing and fMRI.

Interventions

Active Cannabis

400 mg of vaporized and inhaled active cannabis (5.1%)

Placebo Cannabis

400 mg of vaporized and inhaled placebo cannabis (<.1%)

Primary outcome measure

Cerebral Blood Flow (CBF) [ Time Frame: All data will be collected at the single study session (Day 1). ]

Central Contacts and Locations

Central contacts

Madelynn Meredith, BS

619-431-1850 mameredith@health.ucsd.edu

Yasmeen Esshaki, MA

619-786-0375 yesshaki@health.ucsd.edu

Locations

Center for Functional MRI - W.M.Keck Building

Recruiting

La Jolla, California, United States, 92093

Contacts

Madelynn Meredith, BS

619-431-1850 mameredith@health.ucsd.edu

Yasmeen Esshaki, MA

619-786-0375 yesshaki@health.ucsd.edu

Principal Investigator:

Fadel Zeidan, PhD

More Information

Sponsor

University of California, San Diego

Last update posted

Jun 3, 2026

Last verified

Jan, 2026

Keywords

Cannabis
Vaporized cannabis
THC
chronic low back pain

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by University of California, San Diego on 2026-06-03.