Transmutation reactions in highly loaded hydrides have been reported by a number of research groups. These studies are briefly summarized with emphasis on common systematics and key "signatures". Transmutations divide into two types: heavy intermediate compound nucleus reactions yielding an array of products with a large spectrum of masses; direct reactions between H/D and the electrode metal or impurity atoms yielding isolated "single" products. Various mechanisms have been proposed to explain the products and the ability to overcome the extremely large Columbic repulsion of the high-Z elements involved. Here we briefly consider a model involving orbital mixing and virtual neutron formation associated with charge accumulation and hydrogen/deuteron flow at highly loaded interfaces.