Medical active substance patch with reduced optical conspicuousness on the skin

A medical active substance patch comprising a monolayer or multilayer matrix and a backing layer connected with said matrix, said backing layer having one side averted from the skin, at least one layer of the matrix contains a pharmaceutically active substance, and at least one layer of the matrix contains an ingredient selected from the group consisting of at least one colored ingredient and at least one colorless ingredient being colorless in an initial state and tending to discolor or to discolor(s) during storage or to discolor during the application period;

• said at least one colored ingredient and said at least one colorless ingredient are selected from the group consisting of a pharmaceutically active substance and an auxiliary agent;
• wherein said patch has a lightness color value L1 which is not less than 50% and not more than 200% of a lightness color value L2, with L2 being the lightness value of the region of the skin of the same person which surrounds the applied patch, the lightness color values L1 and L2 determined via a tristimulus colorimeter;
• said patch optically masks discoloration due to decomposition promoted by light that begins and intensifies after the patch has been manufactured,
• said patch comprises at least one substance selected from the group consisting of skin tone dyes and pigments,
• said patch is transparent or translucent,
• a surface of the backing layer which is averted from the skin has been provided with reduced reflection properties, and
• the reduced reflection properties are imparted by either physical methods or by applying an antireflection layer or antireflection coating.