Low Dose Naltrexone for Complex Regional Pain Syndrome

If you suffer from CRPS, be sure to indicate this in the survey and include correct and up-to-date contact information for us to get in touch with you.

About the Study

Stanford has been conducting a study to test Low-Dose Naltrexone (LDN), an FDA-approved drug, and Complex Regional Pain Syndrome (CRPS). There is significant evidence to suggest that at low doses it can effectively treat certain types of pain, fatigue, and sleep disorders. This will be the first official study of the effectiveness of LDN for CRPS. 

This is a randomized study, which means that you have a 50/50 chance of receiving the drug treatment. If you are randomized into the control group, you will be offered an opportunity to continue in the study and to receive treatment. 

In-Person Participation

  • 14 weeks; 2 weeks baseline testing, 8 weeks of LDN/placebo treatment, 4 weeks follow up
  • Up to 2 in-person visits to Palo Alto, CA
  • Physical exam
  • Blood draw
  • Sensory testing for heat, cold, and pressure applied to the skin
  • Weekly questionnaires
  • Daily pain score reporting

Remote Participation

  • 14 weeks; 2 weeks baseline testing, 8 weeks of LDN/placebo treatment, 4 weeks follow-up
  • Visits take place over Stanford Zoom Platform
  • Weekly questionnaires
  • Daily pain score reporting
  • LDN/placebo medication will be sent to your home


  • In-person participation: $30/visit up to $60, $25 for blood samples up to two samples, bonus of $100 for completing all study visits.
  • Remote participation: $100 for completing all virtual study visits, daily surveys, and weekly questionnaires.


  • 18-70
  • Diagnosis of CRPS or RSD at least 1 year ago
  • CRPS pain in the arms and/or legs
  • Stable treatment for 1 month
  • Not on opioid pain treatment or narcotics for 1 month before study and for study term
  • No known allergy to naltrexone or naloxone
  • Not being pregnant or planning to become pregnant during the course of the study.

For questions about the study, contact Birutė Gedrimaitė
Email: birute@stanford.edu
Phone: (650)497-0485

For questions regarding participant rights, contact:
Phone: (866) 680-2906