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Low Dose Naloxone
Low-dose naloxone blocks opioid receptors at sub-analgesic concentrations to enhance endogenous opioid signaling and reduce pain and inflammation.
Low-dose naloxone blocks opioid receptors at sub-analgesic concentrations to enhance endogenous opioid signaling and reduce pain and inflammation. Used for Chronic pain (in combination with opioids or as monotherapy), Opioid-induced hyperalgesia and tolerance.
At a glance
| Generic name | Low Dose Naloxone |
|---|---|
| Sponsor | University of Texas Southwestern Medical Center |
| Drug class | Opioid receptor antagonist (low-dose formulation) |
| Target | Toll-like receptor 4 (TLR4); opioid receptors (mu, delta, kappa) at sub-blocking doses |
| Modality | Small molecule |
| Therapeutic area | Pain Management / Neurology |
| Phase | Phase 3 |
Mechanism of action
Naloxone is a competitive opioid receptor antagonist; at very low doses, it selectively blocks toll-like receptor 4 (TLR4) signaling and glial cell activation without fully antagonizing therapeutic opioid effects. This reduces neuroinflammation and glial-mediated pain amplification, potentially enhancing analgesia and reducing opioid tolerance when co-administered with standard opioids or used alone for chronic pain conditions.
Approved indications
- Chronic pain (in combination with opioids or as monotherapy)
- Opioid-induced hyperalgesia and tolerance
Common side effects
- Nausea
- Headache
- Dizziness
- Withdrawal symptoms (if opioid-dependent)
Key clinical trials
- Low-dose Naltrexone for Post-COVID Fatigue Syndrome (PHASE2)
- Combination Gerotherapeutic Interventions for Healthspan Improvement (PHASE3)
- Comparing Outpatient Treatment Retention Among Individuals Using Fentanyl Randomized to Low-dose and Direct-to-inject Buprenorphine Initiation (PHASE4)
- Low Dose Naltrexone (LDN) for Management of Fatigue in Prostate Cancer Patients on Androgen Deprivation Therapy (ADT) (PHASE2)
- Low-Dose Naltrexone For ME/CFS: Dose-Finding (PHASE2)
- iSTEP-N 101b: Pharmacokinetics and Safety Study of Low- and High-Dose Naltrexone Implants vs Monthly Vivitrol in Healthy Volunteers (PHASE1)
- Low Dose Naltrexone to Improve Physical Health in Patients With Vasculitis (PHASE2)
- Phase II Clinical Study on the Efficacy and Safety of Naltrexone Implant in Patients With Alcohol Use Disorder (PHASE2)
Primary sources
Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.
| Source | Used for |
|---|---|
| ClinicalTrials.gov | Trial enrolment, design, endpoints, results |