NSAID-containing external preparation for percutaneous administration and interleukin -1α production inhibitor

And non-steroidal anti-inflammatory agent, a gallic acid alkyl ester, external preparation for percutaneous administration containing a phenolic radical scavenger having a branched-chain lower alkyl group. A phenolic radical scavenger having a branched-chain lower alkyl groups, and / or interleukin -1α production inhibitor comprising a gallic acid alkyl ester.