In a 2012 review, all clinical trials to date were summarized.  In a 2015 analysis of a double blind placebo controlled study of PEA in sciatic pain, the Numbers Needed to Treat was . Its positive influence in chronic pain, and inflammatory states such as atopic eczema, seems to originate mainly from PPAR alpha activation.   Since 2012 a number of new trials have been published, among which studies in glaucoma.   PEA also seems to be one of the factors responsible for the decrease in pain sensitivity during and after sport, comparable to the endogenous opiates (endorphines).