Methods to treat skin conditions and diseases by applying Porifera based compositions to the skin are described. Treatable skin conditions and diseases include acne vulgaris, rosacea, seborrheic dermatitis, atopic dermatitis, psoriasis, photo-aging, actinic keratosis and eczema, also known as atopic dermatitis. Therapeutic compositions are obtained from members of Porifera, for example sponges, specifically, fresh water sponges. An example of a fresh water sponge is Spongilla species. One specific therapeutic composition is obtained from Spongilla species and formulated with pharmaceutical excipients.
