It is preferable that the connexin 26 inhibitor of the present invention be a compound represented by General Formula (1): where R is a hydrogen atom or a hydrocarbon group, X is one of a hydrogen atom, a methansulfonyl group, an ethansulfonyl group, an acetyl group, a trifluoroacetyl group, a hydroxyl group, an alkoxy group and an amino group; m is an integer of from 4 to 10; and n is an integer