<p>The sheet stack (1) is configured so that sheets (10) impregnated with a prescribed drug solution are held as a stack inside a package (20) and the sheets (10) are removed through an opening (21) in the package (20). After the sheet (10) is folded with a first crease (F11) along a first direction (L) as the starting point, the sheet is folded with a second crease (F21) as the starting point. When folded with the second crease (F21) as the starting point, a first region (41) and a second region (42) that is positioned closer to the opening than the first region are provided with the second crease as the boundary. The length (L42) of the second region (42) in the first direction is shorter than the length (L41) of the first region in the first direction.</p>
