Low dose naltrexone for neuropathic pain
Low dose naltrexone is popular in the alternative treatment world. It is a bit strange, as this molecule is quite non-alternative. But low dose naltrexone (LDN) is recommended on lay internetsites for a multitude of diseases, from MS to cancer. That always provokes anti-bodies by doctors, but naltrexone indeed has anti-inflammatory properties. It might be an interesting treatment option for treatment refractory neuropathic pain patients.
Low dose naltrexone, inflammatory response and neuropathic pain
Glia, asterocytes and modulation of inflammatory responses are hot in the search for new treatments for neuropathic pain.   And not only the cannabinoids might work via this mechanism,  low dose naltrexone, popular at the time in patients suffering from MS , might play a role in this pathogenesis. 
The later is quite interesting, it provokes us to rethink the putative role of low dose naltrexone in the treatment of neuropathic pain… 
Let us review the only trial I know assessing the effects of low dose naltrexone in a sort of neuropathic pain: fibromyalgia.
Naltrexone low dose (LDN): a pilot trial
Recently a pilot trial was reported on the efficacy and safety of low dose naltrexone (4.5 mg) in fibromyalgia. Especially patients with a high ESR were found to be responders to the naltrexone theraoy. That is quite fitting with the above hypothesis. Especially since we know patients suffering from fibromyalgia pain also respond positive tp pregabeline.  The authors of the report, Younger and Mackey, conducted a placebo-controlled, single-blind, crossover design study in 10 patients with moderately-severe fibromyalgia, and the dose was 4.5 mg/day.
Naltrexone treatment resulted in 32.5% decrease of overall fibromyalgia symptom severity on the visual analog scale compared with baseline, whereas the reduction was only 2.3% during the placebo phase (P<0.0005 versus baseline and P=0.003 versus placebo).  More details on the site of Stanford.
And the same dose seemed to inhibit the symptoms of Crohn’s disease.
Thus, LDN, 3-4.5 mg/day a.n. might be an interesting therapeutic option for patients refractory to other pharmacological interventions.
LDN in our clinic
Meanwhile we gained positive experience prescribing 1-2.5 mg LDN, sometimes in combination with a gift of tramadol 12 hours later. That might boost the analgesic effects even more. Especially in overweight, obese individuals suffering from neuropathic pain, this regime worked quite impressive in our hands. But mostly in combination with the supplement palitoylethanolamide (PeaPure).
August 2010, Jan M. Keppel Hesselink, MD, PhD , revision feb 2014
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