A skin care composition can include a growth factor, such as an epidermal and/or keratinocyte growth factor (EGF, KGF), a DNA repair enzyme encapsulated by a liposome, and a carrier suitable for topical administration of the EGF and/or KGF and DNA repair enzyme to a subjects skin. One, two, or more modalities, such as sonophoresis, can be used to synergistically increase transdermal penetration of compositions. Also disclosed herein is a therapeutic agent for preventing or treating a condition of the gastrointestinal tract.
