The objective of the present invention is to provide a method of preventing an oxygen-caused alteration of a drug in an adhesive patch enclosed inside a packaging container. The present invention is a package body comprising a packaging container and a drug-containing adhesive patch enclosed inside the packaging container, wherein the amount of oxygen gas inside the package body is 20 μL or less, and the concentration of oxygen gas is 17.0 to 25.0 vol %. This packaging does not have to contain an oxygen scavenger as a separate member distinct from the drug-containing adhesive patch. Further, the amount of oxygen gas may be 4 μL/mg or less per amount of a drug in the drug-containing adhesive patch.