Our Achy Bee pain rub, made with Japanese peppermint oil works so well to ease pain in muscles, in headaches and even in stomachaches ( just roll it on your tummy.) I knew it worked from making and using it myself, but I have wondered about the chemical actions that make peppermint oil so effective. Here's one answer: A research abstract from a 2012 issue of Pain journal describes a study that found that menthol blocks sodium pain receptor channels...
http://www.ncbi.nlm.nih.gov/pubmed/22172548
