Therapeutic importance of low doses of naltrexone in multiple sclerosis Review article

Abstract

Naltrexone (NTX), as an opioid receptor antagonist, is a drug used to treat opioid and alcohol addiction. In recent years, there has been interested in naltrexone therapy used at lower than registered doses (1–5 mg/day). Low-dose naltrexone (LDN) differs from the indications for higher-dose naltrexone, and LDN is used off-label. The mechanism of action of LDN is not fully understood. Still, the results of several studies indicate that, although it affects the same receptors, it differs from the mechanism of action of NTX used at higher doses. It has been shown that LDN can exhibit anti-inflammatory, immunomodulatory and anti-tumour effects. The results of these studies indicate that LDN may have positive effects in patients with multiple sclerosis (MS) and the treatment of other diseases (e.g. Crohn’s disease, psoriasis, fibromyalgia, cancer and pain of various origins). The present paper reviews and analyses the available studies on the use of LDN in MS.