A review of adverse events in animals and children after secondary exposure to transdermal hormone-containing medicinal products.

Background: Hormonal replacement therapy is widely used to treat conditions in humans, the most well-known indication being the relief of menopausal symptoms in women. Many of the hormone-containing products (HCP) are applied to the skin. This transdermal delivery poses a risk to animals and humans through secondary exposure, especially when product information is not strictly followed.