Chronic PainNCT03677206
The Effect of Light Therapy on Chronic Pain
A study testing Exposure to green LED light and Exposure to white LED light in people with Chronic Pain, run by University of Arizona at 1 site in United States.
Trial summary
Chronic pain is a major problem in the USA and the rest of the world, currently, all available pharmacological interventions carry with them significant side effects. Pain clinics are specially equipped to perform intentional pain procedures to manage pain. Read more about this study
- Who is it for?
- Ages 18 to 80 years
- Conditions the study is for
- Chronic Pain
- What is being tested?
- Exposure to green LED light and Exposure to white LED light
- Type of treatment
- Medical device
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 55 participants
- Where
- 1 siteUnited States
- Study dates
- Jun 2016to Dec 2026
- Phase
- Interventional
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 80 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Adults ages 18 - 80 able to understand English and comply with study protocol
- Peripheral neuropathy from HIV or chemotherapy.
- History of fibromyalgia
- Headaches
- Chronic Pain
- 7-day average numeric pain score of 5/10 or greater at baseline evaluation
Who cannot join
- Subjects receiving remuneration for their pain treatment
- Subjects that are incarcerated
- Subjects unable to read English and complete assessments
- Addictive behavior, severe clinical depression, or psychotic features
Trial locations and contacts
1 site in 1 country.
United States1 site
Banner University Medical Center South
Tucson, Arizona, 85713
About this study
Chronic pain is a major problem in the USA and the rest of the world, currently, all available pharmacological interventions carry with them significant side effects. Pain clinics are specially equipped to perform intentional pain procedures to manage pain. However, there remain groups of patients what neither benefit from pharmacological nor from interventional pain procedures. Other methods have shown only minor benefits such as hypnosis or cognitive behavioral therapy. Therefore, other techniques need to be investigated.
Light therapy has been shown to have significant biological effects on humans. For example, light therapy is used to manage depression. Several clinical trials have shown that certain wavelengths of light can improve wound healing, decrease temporomandibular joint dysfunction (TMJ) pain, and decrease fear of back pain. In these trials, light was directed at the site of pain. In an attempt to better understand the effect of different wavelengths of light, pre-clinical studies were conducted using rats. The investigators have shown green and blue Light emitting diode, (LED) light produced antinociception (analgesia) and reversed neuropathic pain associated with several models of chronic pain. The analgesic effect of light was completely blocked when rats had their eyes covered, this suggests that the analgesic effects seen are mainly due to systemic effect through the visual system.
Read more
Preliminary experiments on rats suggest that this effect is mediated through the endogenous opioids and cannabinoid system.
The investigators believe that LED light is a safe alternative to pharmacological intervention to manage pain by stimulating the endogenous endorphin and cannabinoid systems. The investigators initial target participants with history of HIV, chemotherapy induced peripheral neuropathy and fibromyalgia. Participants will be divided into 2 groups. The first group will be a control group exposed to white LED light. The second group will be exposed to green LED light, respectively. Participants will be asked to take LED light home and will be asked to set in a dark room for 2 hours daily for 3 months with their LED light on. At the end of the 3 months trial, the investigator will assess their pain intensity, analgesic use, and overall quality of life. The investigators hypothesis is that participants exposed to green and blue light will have less use of analgesics and will have better life quality.
Read the detailed description
During the initial visit, the investigator will collect several pieces of data from participants that are considered part of the routine care, if you are being seen in the clinic, this information will also be used for research purposes. Initially the investigator will ask participants to provide their age, gender, work status, disability status, type of work, whether a previous pain physician has evaluated or provided treatment in the past, if there is any ongoing litigation, a detailed description of the pain (burning, electrical, shooting…etc.) and its location. If the participants are being seen in the clinic for their normal care a detailed physical examination assessing the motor strength of the upper extremities, sensation to light touch and reflexes that is part of the standard of care will be provided for the participants. The participants will be asked to give a numerical value for their pain (a scale from 0-10 where 0 is no pain and 10 is the worst pain imagined). Two questionnaires will be provided for the participants to complete which are not standard of care. The first one is the EuroQol Group (EQ-5D) which provide an over assessment of the quality of life. The second is a medication log to document their analgesics use. If the participants are being evaluated via telephone call, the same questions will be conducted, but no physical exam will be provided.
The participants will be assigned to either a white, or green light group. The participants have 50% chance of being in either group. Once the participants are assigned a light group, the participants will be given a strip of Light emitting diode, (LED) light that correspond to their color group. The participants will be asked to take and use the LED strip in a dark room in their house every day for two hours to be exposed to the light, the participants will do this for 10 weeks. The study start date and the outcome assessment timeline will begin from the date of your first exposure to the assigned light. The participants will be asked to complete their weekly questionnaires and daily log, these will be given to the participants on their first clinic visit or sent to the participants if they live out of town. There will be several follow up appointments as detailed below. There is a chance the participants may be asked to cross over into a different group from the one the participants were assigned, there will we a 2 week washout period, then return to clinic for light assignment then light exposure for 10 week, similar visits as described below.
For the follow up clinic visit or phone call (Week 10), data similar to the information gathered at the initial visit will be collected. The description of the pain (burning, electrical, shooting…etc.) and its location will be reviewed. A physical examination assessing for pain and sensation to light touch that is part of the standard of care will be provided for the participants. At the end of the study, the participants will be asked to return the LED strip, their logs and questionnaires.
There is an optional blood draw and saliva sample collection for patients that consent to this. Blood and saliva samples will be collected at baseline and end of study, blood draws will be done to look for inflammatory mediators, increased anti inflammatory mediators and endocannabinoids. Saliva samples will be collected to check for melatonin.
- Conditions
- Chronic Pain
- Being tested
- Exposure to green LED light, Exposure to white LED light
- Medical subject headings
- Chronic Pain
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Exposure to green LED lightDevice
Participants will be exposed to green LED strip lights in a dark room for 2 hours a day.
Exposure to white LED lightDevice
Participants will be exposed to white LED strip lights in a dark room for 2 hours a day.
| Study group | Role | What they receive |
|---|---|---|
| Exposure to white LED light. | Sham comparator | Subjects will exposed to white light provided to them, in their homes in a dark room for approximately 2 hours for 10 weeks Receives: Device: Exposure to white LED light |
| Exposure to green LED light | Experimental | Subjects will exposed to green light provided to them, in their homes in a dark room for approximately 2 hours for 10 weeks. Receives: Device: Exposure to green LED light |
| Cross over | Other | Subject will be exposed to white light (sham) for 10 weeks, then have a wash out period for 2 weeks, then exposed to green light (experimental) for 10 weeks. Receives: Device: Exposure to green LED light; Device: Exposure to white LED light |
What is being measured
The primary outcome is the main question the study is designed to answer.
For Chronic Pain
Change in the intensity of chronic pain as measured by the Numerical Pain Scale (NPS). The NPS has a value ranging from 0 to 10 out of a maximum of 10. 0 means no pain. 10 means the most severe pain.
Measured: baseline and 10 - 22 weeks, depending on study arm
Secondary outcomes (3)
Fibromyalgia Impact Questionnaire
Change in Fibromyalgia Impact Questionnaire (FIQ) total score. The FIQ is a validated, self-reported measure assessing physical functioning, work status, depression, anxiety, sleep, pain, stiffness, fatigue, and well-being over the past week. Scores range from 0 to 100, with higher scores indicating greater impairment.
Measured: baseline and 10 - 22 weeks, depending on study arm
Headache Impact Test-6
Change in Headache Impact Test-6 (HIT-6) total score from baseline to 10-22 weeks. The HIT-6 is a 6-item questionnaire designed to assess the impact of headaches on daily life, including pain severity, disability, and emotional effects over the past 4 weeks. Scores range from 36 to 78, where 36-49 indicates little or no impact, 50-55 indicates some impact, 56-59 reflects substantial impact, and 60-78 indicates severe impact requiring intervention. A higher score indicates greater headache impact.
Measured: baseline and 10 - 22 weeks, depending on study arm
EQ-5D-5L
Change in health-related quality of life as measured by the EQ-5D-5L. The EQ-5D-5L is a standardized, patient-reported outcome measure that assesses health-related quality of life across five dimensions (mobility, self-care, usual activities, pain/discomfort, and anxiety/depression), each rated on a 5-level scale (no problems to extreme problems). The score is calculated using a country-specific value set to produce a single index value ranging from -0.594 (worse than death) to 1.0 (perfect health), where higher scores indicate better health status.
Measured: baseline and 10 - 22 weeks, depending on study arm
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted19 Sep 2018
- Study startJun 2016
- Primary completionJun 2023
- Study completionDec 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Publications (8)Papers the sponsor has linked to this study.
- Other trials for Chronic PainStudies of the same condition, open and under way.
- More trials run by University of ArizonaThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Supportive care
- Allocation
- Randomised
- Intervention model
- Crossover
- Model description
- Initially, patients will receive White LED exposure, then they will be crossed over to Green LED exposure. The patients will not be told which one is the treatment and which one is the control.
- Masking
- Single blind
- Who is masked
- Investigator
- Enrolment
- 55 participants (actual)
Sponsor and investigators
- Lead sponsor
- University of Arizona
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Mohab Ibrahim, PhD MD, University of Arizona
- Investigators
- Mohab Ibrahim, PhD., MD, Principal investigator, University of Arizona
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT03677206
- Sponsor's protocol ID
- 1604514512
- Status last verified
- Nov 2025
- First submitted
- 11 May 2017
- Last updated
- 18 Nov 2025
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- No
- Individual data sharing
- No
Publications
Institute of Medicine (US) Committee on Advancing Pain Research, Care, and Education. Relieving Pain in America: A Blueprint for Transforming Prevention, Care, Education, and Research. Washington (DC): National Academies Press (US); 2011. Available from http://www.ncbi.nlm.nih.gov/books/NBK91497/
PubMed 22553896Hooley JM, Franklin JC, Nock MK. Chronic pain and suicide: understanding the association. Curr Pain Headache Rep. 2014;18(8):435. doi: 10.1007/s11916-014-0435-2.
PubMed 24916035Hassett AL, Aquino JK, Ilgen MA. The risk of suicide mortality in chronic pain patients. Curr Pain Headache Rep. 2014;18(8):436. doi: 10.1007/s11916-014-0436-1.
PubMed 24952608Smith AA, Friedemann ML. Perceived family dynamics of persons with chronic pain. J Adv Nurs. 1999 Sep;30(3):543-51. doi: 10.1046/j.1365-2648.1999.01123.x.
PubMed 10499210Gray D, Coon H, McGlade E, Callor WB, Byrd J, Viskochil J, Bakian A, Yurgelun-Todd D, Grey T, McMahon WM. Comparative analysis of suicide, accidental, and undetermined cause of death classification. Suicide Life Threat Behav. 2014 Jun;44(3):304-16. doi: 10.1111/sltb.12079.
PubMed 25057525Hwang MH, Shin JH, Kim KS, Yoo CM, Jo GE, Kim JH, Choi H. Low level light therapy modulates inflammatory mediators secreted by human annulus fibrosus cells during intervertebral disc degeneration in vitro. Photochem Photobiol. 2015 Mar-Apr;91(2):403-10. doi: 10.1111/php.12415. Epub 2015 Jan 26.
PubMed 25557915Martin L, Porreca F, Mata EI, Salloum M, Goel V, Gunnala P, Killgore WDS, Jain S, Jones-MacFarland FN, Khanna R, Patwardhan A, Ibrahim MM. Green Light Exposure Improves Pain and Quality of Life in Fibromyalgia Patients: A Preliminary One-Way Crossover Clinical Trial. Pain Med. 2021 Feb 4;22(1):118-130. doi: 10.1093/pm/pnaa329.
PubMed 33155057Martin LF, Patwardhan AM, Jain SV, Salloum MM, Freeman J, Khanna R, Gannala P, Goel V, Jones-MacFarland FN, Killgore WD, Porreca F, Ibrahim MM. Evaluation of green light exposure on headache frequency and quality of life in migraine patients: A preliminary one-way cross-over clinical trial. Cephalalgia. 2021 Feb;41(2):135-147. doi: 10.1177/0333102420956711. Epub 2020 Sep 9.
PubMed 32903062
Study at a glance
From the registry record, last updated by the sponsor on 18 Nov 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- The Effect of Light Therapy on Chronic Pain
- ClinicalTrials.gov ID
- NCT03677206
- Acronym / sponsor ID
- 1604514512
- Conditions
- Chronic Pain
- Study type
- Interventional
- Recruitment status
- Active, not recruiting
- Enrolment
- 55 participants (actual)
- Lead sponsor
- University of ArizonaUniversity, hospital or other
- Study start
- Jun 2016 (actual)
- Primary completion
- Jun 2023 (actual)
- Study completion
- Dec 2026 (estimated)
- First posted
- 19 Sep 2018 (actual)
- Results
- Posted 18 Nov 2025
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Chronic pain is a major problem in the USA and the rest of the world, currently, all available pharmacological interventions carry with them significant side effects. Pain clinics are specially equipped to perform intentional pain procedures to manage pain. However, there remain groups of patients what neither benefit from pharmacological nor from interventional pain procedures. Other methods have shown only minor benefits such as hypnosis or cognitive behavioral therapy. Therefore, other techniques need to be investigated.
Light therapy has been shown to have significant biological effects on humans. For example, light therapy is used to manage depression. Several clinical trials have shown that certain wavelengths of light can improve wound healing, decrease temporomandibular joint dysfunction (TMJ) pain, and decrease fear of back pain. In these trials, light was directed at the site of pain. In an attempt to better understand the effect of different wavelengths of light, pre-clinical studies were conducted using rats. The investigators have shown green and blue Light emitting diode, (LED) light produced antinociception (analgesia) and reversed neuropathic pain associated with several models of chronic pain. The analgesic effect of light was completely blocked when rats had their eyes covered, this suggests that the analgesic effects seen are mainly due to systemic effect through the visual system.
Preliminary experiments on rats suggest that this effect is mediated through the endogenous opioids and cannabinoid system.
The investigators believe that LED light is a safe alternative to pharmacological intervention to manage pain by stimulating the endogenous endorphin and cannabinoid systems. The investigators initial target participants with history of HIV, chemotherapy induced peripheral neuropathy and fibromyalgia. Participants will be divided into 2 groups. The first group will be a control group exposed to white LED light. The second group will be exposed to green LED light, respectively. Participants will be asked to take LED light home and will be asked to set in a dark room for 2 hours daily for 3 months with their LED light on. At the end of the 3 months trial, the investigator will assess their pain intensity, analgesic use, and overall quality of life. The investigators hypothesis is that participants exposed to green and blue light will have less use of analgesics and will have better life quality.
Detailed description
During the initial visit, the investigator will collect several pieces of data from participants that are considered part of the routine care, if you are being seen in the clinic, this information will also be used for research purposes. Initially the investigator will ask participants to provide their age, gender, work status, disability status, type of work, whether a previous pain physician has evaluated or provided treatment in the past, if there is any ongoing litigation, a detailed description of the pain (burning, electrical, shooting…etc.) and its location. If the participants are being seen in the clinic for their normal care a detailed physical examination assessing the motor strength of the upper extremities, sensation to light touch and reflexes that is part of the standard of care will be provided for the participants. The participants will be asked to give a numerical value for their pain (a scale from 0-10 where 0 is no pain and 10 is the worst pain imagined). Two questionnaires will be provided for the participants to complete which are not standard of care. The first one is the EuroQol Group (EQ-5D) which provide an over assessment of the quality of life. The second is a medication log to document their analgesics use. If the participants are being evaluated via telephone call, the same questions will be conducted, but no physical exam will be provided.
The participants will be assigned to either a white, or green light group. The participants have 50% chance of being in either group. Once the participants are assigned a light group, the participants will be given a strip of Light emitting diode, (LED) light that correspond to their color group. The participants will be asked to take and use the LED strip in a dark room in their house every day for two hours to be exposed to the light, the participants will do this for 10 weeks. The study start date and the outcome assessment timeline will begin from the date of your first exposure to the assigned light. The participants will be asked to complete their weekly questionnaires and daily log, these will be given to the participants on their first clinic visit or sent to the participants if they live out of town. There will be several follow up appointments as detailed below. There is a chance the participants may be asked to cross over into a different group from the one the participants were assigned, there will we a 2 week washout period, then return to clinic for light assignment then light exposure for 10 week, similar visits as described below.
For the follow up clinic visit or phone call (Week 10), data similar to the information gathered at the initial visit will be collected. The description of the pain (burning, electrical, shooting…etc.) and its location will be reviewed. A physical examination assessing for pain and sensation to light touch that is part of the standard of care will be provided for the participants. At the end of the study, the participants will be asked to return the LED strip, their logs and questionnaires.
There is an optional blood draw and saliva sample collection for patients that consent to this. Blood and saliva samples will be collected at baseline and end of study, blood draws will be done to look for inflammatory mediators, increased anti inflammatory mediators and endocannabinoids. Saliva samples will be collected to check for melatonin.
Study design
- Primary purpose
- Supportive care
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Single blind (investigator)
- Number of arms
- 3
- Model description
- Initially, patients will receive White LED exposure, then they will be crossed over to Green LED exposure. The patients will not be told which one is the treatment and which one is the control.
| Arm | Type | Receives |
|---|---|---|
| Exposure to white LED light. | Sham comparator | Device: Exposure to white LED lightSubjects will exposed to white light provided to them, in their homes in a dark room for approximately 2 hours for 10 weeks |
| Exposure to green LED light | Experimental | Device: Exposure to green LED lightSubjects will exposed to green light provided to them, in their homes in a dark room for approximately 2 hours for 10 weeks. |
| Cross over | Other | Device: Exposure to green LED light, Device: Exposure to white LED lightSubject will be exposed to white light (sham) for 10 weeks, then have a wash out period for 2 weeks, then exposed to green light (experimental) for 10 weeks. |
Who may qualify
- Ages
- 18 to 80 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (6 listed)
- Adults ages 18 - 80 able to understand English and comply with study protocol
- Peripheral neuropathy from HIV or chemotherapy.
- History of fibromyalgia
- Headaches
- Chronic Pain
Key exclusion criteria (4 listed)
- Subjects receiving remuneration for their pain treatment
- Subjects that are incarcerated
- Subjects unable to read English and complete assessments
- Addictive behavior, severe clinical depression, or psychotic features
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Exposure to green LED lightParticipants will be exposed to green LED strip lights in a dark room for 2 hours a day. | Device | Cross over, Exposure to green LED light |
| Exposure to white LED lightParticipants will be exposed to white LED strip lights in a dark room for 2 hours a day. | Device | Cross over, Exposure to white LED light. |
Primary outcome
For Chronic Pain
Time frame: baseline and 10 - 22 weeks, depending on study arm
Change in the intensity of chronic pain as measured by the Numerical Pain Scale (NPS). The NPS has a value ranging from 0 to 10 out of a maximum of 10. 0 means no pain. 10 means the most severe pain.
3 secondary outcomes
Fibromyalgia Impact Questionnaire
Time frame: baseline and 10 - 22 weeks, depending on study arm
Headache Impact Test-6
Time frame: baseline and 10 - 22 weeks, depending on study arm
EQ-5D-5L
Time frame: baseline and 10 - 22 weeks, depending on study arm
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 18 Nov 2025.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- Background: PubMed 22553896Institute of Medicine (US) Committee on Advancing Pain Research, Care, and Education. Relieving Pain in America: A Blueprint for Transforming Prevention, Care, Education, and Research. Washington (DC): National Academies Press (US); 2011. Available from http://www.ncbi.nlm.nih.gov/books/NBK91497/
- Background: PubMed 24916035Hooley JM, Franklin JC, Nock MK. Chronic pain and suicide: understanding the association. Curr Pain Headache Rep. 2014;18(8):435. doi: 10.1007/s11916-014-0435-2.
- Background: PubMed 24952608Hassett AL, Aquino JK, Ilgen MA. The risk of suicide mortality in chronic pain patients. Curr Pain Headache Rep. 2014;18(8):436. doi: 10.1007/s11916-014-0436-1.
- Results publication: PubMed 10499210Smith AA, Friedemann ML. Perceived family dynamics of persons with chronic pain. J Adv Nurs. 1999 Sep;30(3):543-51. doi: 10.1046/j.1365-2648.1999.01123.x.
- Results publication: PubMed 25057525Gray D, Coon H, McGlade E, Callor WB, Byrd J, Viskochil J, Bakian A, Yurgelun-Todd D, Grey T, McMahon WM. Comparative analysis of suicide, accidental, and undetermined cause of death classification. Suicide Life Threat Behav. 2014 Jun;44(3):304-16. doi: 10.1111/sltb.12079.
- Results publication: PubMed 25557915Hwang MH, Shin JH, Kim KS, Yoo CM, Jo GE, Kim JH, Choi H. Low level light therapy modulates inflammatory mediators secreted by human annulus fibrosus cells during intervertebral disc degeneration in vitro. Photochem Photobiol. 2015 Mar-Apr;91(2):403-10. doi: 10.1111/php.12415. Epub 2015 Jan 26.
- Derived from this study: PubMed 33155057Martin L, Porreca F, Mata EI, Salloum M, Goel V, Gunnala P, Killgore WDS, Jain S, Jones-MacFarland FN, Khanna R, Patwardhan A, Ibrahim MM. Green Light Exposure Improves Pain and Quality of Life in Fibromyalgia Patients: A Preliminary One-Way Crossover Clinical Trial. Pain Med. 2021 Feb 4;22(1):118-130. doi: 10.1093/pm/pnaa329.
- Derived from this study: PubMed 32903062Martin LF, Patwardhan AM, Jain SV, Salloum MM, Freeman J, Khanna R, Gannala P, Goel V, Jones-MacFarland FN, Killgore WD, Porreca F, Ibrahim MM. Evaluation of green light exposure on headache frequency and quality of life in migraine patients: A preliminary one-way cross-over clinical trial. Cephalalgia. 2021 Feb;41(2):135-147. doi: 10.1177/0333102420956711. Epub 2020 Sep 9.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Mohab Ibrahim, PhD., MD principal investigator
University of Arizona
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Exposure to green LED light and Exposure to white LED light in people with Chronic Pain, run by University of Arizona at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 6 inclusion and 4 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: under way, not looking for participants, as of the sponsor's last update on 18 Nov 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
Yes. Results are posted in the registry (first posted 18 Nov 2025). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
For Chronic Pain (time frame: baseline and 10 - 22 weeks, depending on study arm). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT03677206, which also lists 8 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 18 Nov 2025; AzTrials last refreshed its copy on 6 Nov 2026.