The Effects of Low Dose Naltrexone in Children with Chronic Pain

Background: Naltrexone is an FDA-approved opioid antagonist. At one-tenth the usual dosage, it is thought to have antinociceptive effects mediated through microglial cell inactivation, which can be helpful for chronic pain states, such as fibromyalgia, in adults.[1,2] The percentage of youth that are affected from chronic pain conditions is estimated to be at 15-35%.[3] The present study is the first to examine the efficacy of low-dose naltrexone (LDN) in treating chronic pain in pediatric patients.

Methods: A retrospective chart review was conducted on pediatric patients who were prescribed LDN between 2019 and 2022 for a chronic pain condition. At the start of LDN treatment and for each pain-clinic visit in the subsequent year, pain scores and functional disability inventory (FDI) scores were collected. Multilevel cumulative logit models and multilevel linear models were used to determine the effect of time of LDN on pain and FDI scores, respectively.

Results: There were 168 patients who met inclusion criteria. As compared to visits without LDN, there was no statistically significant difference in pain scores for visits in which the patient had been on LDN for 0-2 months (p=0.88) or for ≥2 months (p=0.25). As compared to visits without LDN, FDI scores significantly decreased after taking LDN for ≥2 months (p< 0.001) but not for 0-2 months (p=0.12).

Conclusion: Children who took LDN had a significant improvement in daily function as compared to before taking LDN.

Citations:

1. Parkitny, L., & Younger, J. (2017). Reduced Pro-Inflammatory Cytokines after Eight Weeks of Low-Dose Naltrexone for Fibromyalgia. Biomedicines, 5(2), 16. https://doi.org/10.3390/biomedicines50200162. YOUNGER, J., NOOR, N., MCCUE, R., MACKEY, S. (2013). LOW-DOSE NALTREXONE FOR THE TREATMENT OF FIBROMYALGIA. ARTHRITIS AND RHEUMATISM. HTTPS://DOI.ORG/10.1002/ART.37734
2. KING, S., CHAMBERS, C. T., HUGUET, A., MACNEVIN, R. C., MCGRATH, P. J., PARKER, L., & MACDONALD, A. J. (2011). THE EPIDEMIOLOGY OF CHRONIC PAIN IN CHILDREN AND ADOLESCENTS REVISITED: A SYSTEMATIC REVIEW. PAIN, 152(12), 2729–2738.