People who have had Alpha hydroxy acid (AHA), isotretionine, vit. A treatment in the last one month, people with skin cancer, warts, solar ketaosis and active skin infection, people with bleeding problems and those on blood thinners, people receiving chemotherapy, radiotherapy or corticotherapy, people with uncontrolled diabetes, people who have had a cosmetic facial surgery in the last 6 months, people with keloid (abnormal wound healing due to excessive cell proliferation) cannot have Dermapen treatment.