
Low Dose Naltrexone
An old ,but new, frontier

Repurposing pharmaceuticals is a common practice, often preferred due to faster FDA approval and easier prescribing. Some medications, however, show promise for treating conditions beyond their original uses and approvals.
​
Naltrexone, developed by Endo Laboratories in the 1960s, was FDA-approved for alcohol and opioid addiction treatment. It works by blocking the brain’s pleasure response to these substances, helping individuals reduce or stop use. While not a cure, it is a valuable tool in addiction recovery.
​
Recently, researchers have explored Naltrexone’s potential at lower doses for other conditions. Standard 50mg doses effectively block euphoric effects, but scientists are investigating the benefits of much smaller doses.
Dr. Bernard Bihari pioneered the off-label use of Low Dose Naltrexone (LDN), administering 4.5 mg to help manage AIDS-related inflammation. Since then, LDN has gained traction for conditions like fibromyalgia, Crohn’s disease, multiple sclerosis, and chronic pain disorders.
​
But how can a drug that blocks opioid effects also relieve pain and inflammation? The answer lies in its mechanism. In individuals not using opioids, low doses of Naltrexone temporarily reduce opioid receptor activity, tricking the body into thinking endorphin production has dropped. In response, the body compensates by increasing endorphin levels, leading to reduced pain and inflammation. LDN’s short duration and low dosage also minimize adverse effects, making it an attractive option for autoimmune disorders and even cancer research.
Despite its potential, LDN remains unapproved by the FDA. However, ongoing research and clinical trials suggest that it could soon become a recognized treatment option in modern medicine.
​
​
References:
Center for Substance Abuse Treatment. Incorporating Alcohol Pharmacotherapies into Medical Practice. Rockville.Chapter 4.Substance Abuse and Mental Health Services Administration
The use of low-dose naltrexone (LDN) as a novel anti-inflammatory treatment for chronic pain:Jarred Younger, Luke Parkitny, and David McLain
Low-Dose Naltrexone (LDN)—Review of Therapeutic Utilization:Karlo Toljan, and Bruce Vrooman