Exhibit

We consent to the incorporation by reference in the Registration Statement (Form S-8) pertaining to the 2015 Equity Incentive Plan and the 2015 Employee Stock Purchase Plan of Flex Pharma, Inc. of our report dated March 6, 2019, with respect to the consolidated financial statements of Flex Pharma, Inc. included in its Annual Report (Form 10-K) for the year ended December 31, 2018, filed with the Securities and Exchange Commission.