Provided is a patch that ensures high storage stability of donepezil or a salt thereof and allows stable transdermal administration of the donepezil or salt thereof in an amount that provides a pharmaceutical effect. The patch includes a substrate 1 and an adhesive layer 2 stacked on and integrated with one surface of the substrate 1 and containing donepezil or a salt thereof and an acrylic adhesive containing a copolymer obtained by copolymerizing monomers that each contain a (meth)acrylic acid ester of a saturated aliphatic alcohol and do not contain vinylpyrrolidone.