Palmitoylethanolamide in the Treatment of Failed Back Surgery Syndrome

INTRODUCTION: This observational study was designed to evaluate the efficacy of ultramicronized palmitoylethanolamide (um-PEA) (Normast®) administration, as add-on therapy for chronic pain, in the management of pain-resistant patients affected by failed back surgery syndrome. METHODS: A total of 35 patients were treated with tapentadol (TPD) and pregabalin (PGB). One month after the start of standard treatment, um-PEA was added for the next two months. Pain was evaluated by the Visual Analogue Scale (VAS) at the time of enrollment (T(0)) and after one (T(1)), two (T(2)), and three (T(3)) months. RESULTS: After the first month with TDP + PGB treatment only, VAS score decreased significantly from 5.7 ± 0.12 at the time of enrollment (T(0)) to 4.3 ± 0.11 (T(1)) (p < 0.0001); however, it failed to provide significant subjective improvement in pain symptoms. Addition of um-PEA led to a further and significant decrease in pain intensity, reaching VAS scores of 2.7 ± 0.09 (T(2)) and 1.7 ± 0.11 (T(3), end of treatment) (p < 0.0001) without showing any side effects. CONCLUSIONS: This observational study provides evidence, albeit preliminary, for the efficacy and safety of um-PEA (Normast) as part of a multimodal therapeutic regimen in the treatment of pain-resistant patients suffering from failed back surgery syndrome.