Efficacy of a Combination of N-Palmitoylethanolamide, Beta-Caryophyllene, Carnosic Acid, and Myrrh Extract on Chronic Neuropathic Pain: A Preclinical Study.

Neuropathic pain (NP) is a common public health problem that poses a major challenge to basic scientists and health-care providers. NP is a complex problem with an unclear etiology and an often-inadequate response to current medications. Despite the high number of drugs available, their limited pharmacological efficacy and side effects hamper their chronic use. Thus, the search for novel treatments is a priority. In addition to pharmaceuticals, natural extracts and food supplements are often used to help treating patients with NP. One such supplement is Noxiall, a commercially available combination of N-Palmitoylethanolamide (PEA), beta-caryophyllene; carnosic acid and myrrh. Here, we compare the efficacy of Noxiall to that of the medications gabapentin and pregabalin in the NP model of chronic constriction injury (CCI) using sciatic nerve ligation in mouse. Following CCI, mice developed a significant increase in mechanical allodynia and thermal hyperalgesia. Results showed that administration of either Noxiall, pregabalin, or gabapentin significantly attenuated mechanical allodynia. The magnitude of the Noxiall effect was comparable to that of gabapentin or pregabalin. In addition, co-administration of non-effective doses of pregabalin and Noxiall resulted in a significant decrease in NP, suggesting an additive efficacy. Noxiall was efficacious also in reducing CCI-induced thermal hyperalgesia. These findings support the rationale of using natural remedies in conjunction with classical pharmacological agents to treat chronic NP.