Atopica is an immunosuppressant and increases the risk of infection for animals and humans alike when contacted. When on this medication, pets are more exposed to infection and are required to avoid other animals or people with contagious diseases or disorders. This is the main reason behind cancer being one of the side effects of this medication. This is why pet parents are advised to wash their hands after applying Atopica to their pets. For more protection, it's recommended to wear latex gloves while administering this medication.