Palo Alto, California 94304


The investigators are testing treatment with low-dose naltrexone (LDN) for symptom relief of complex regional pain syndrome (CRPS). Study participants will be randomly assigned to receive either LDN or placebo for a period of several weeks. During this period participants will be asked to come to several visits, which will include sensory testing, physical assessments, and questionnaires.


Inclusion Criteria: - Upper and/or lower extremity CRPS - On stable treatment for 3 months - CRPS for at least 1 year - Meet the Budapest criteria for CRPS at time of the study. Exclusion Criteria: - Any known allergy to naltrexone or naloxone - Use of prescription opioid analgesics or illegal opioid use - Current of planned pregnancy.

Study is Available At:

Original ID:




Secondary ID:

Study Acronym:


Brief Title:

Low-Dose Naltrexone for the Treatment of Complex Regional Pain Syndrome

Official Title:

Low-Dose Naltrexone for the Treatment of Complex Regional Pain Syndrome

Overall Status:


Study Phase:




Minimum Age:

18 Years

Maximum Age:

65 Years

Quick Facts

Healthy Volunteers
Oversight Has DMC
Study Is FDA Regulated
Study Is Section 801
Has Expanded Access

Study Source:

Stanford University

Oversight Authority:

United States: Food and Drug Administration

Reasons Why Stopped:

Study Type:


Study Design:

Number of Arms:


Number of Groups:


Total Enrollment:


Enrollment Type:


Overall Contact Information

Official Name:Sean Mackey, MD, PhD
Principal Investigator
Stanford University
Primary Contact:Aaron Yue, MD
(650) 497-0485

Study Dates

Start Date:June 2015
Completion Date:June 2019
Completion Type:Anticipated
Primary Completion Date:June 2019
Primary Completion Type:Anticipated
Verification Date:March 2019
Last Changed Date:March 18, 2019
First Received Date:July 15, 2015

Study Outcomes

Outcome Type:Primary Outcome
Measure:Changes in pain severity
Time Frame:Approximately 4 weeks after conclusion of treatment.
Safety Issues:False
Description:Daily pain reports on a 0-10 numerical rating scale for pain, where 0=no pain and 10=pain as bad as you can imagine

Study Interventions

Intervention Type:Drug
Arm Name:LDN
Intervention Type:Drug
Description:Sugar pill
Arm Name:Placebo

Study Arms

Study Arm Type:Placebo Comparator
Arm Name:Placebo
Description:Sugar pill
Study Arm Type:Experimental
Arm Name:LDN
Description:Naltrexone HCL, 4.5 mg, Once a day.

Study Agencies

Agency Class:Other
Agency Type:Lead Sponsor
Agency Name:Stanford University

Sample and Retention Information

There are no available Sample and Retention Information

Study References

There are no available Study References

Data Source:

Date Processed: January 21, 2020

Modifications to this listing: Only selected fields are shown, please use the link below to view all information about this clinical trial.

If you would like to be contacted by the clinical trial representative please fill out the form below.