Abstract: Provided herein is a microstructure array comprising a plurality of dissolving microstructures such as microprojections attached to a base. The plurality of microstructures comprise an active agent in a biocompatible and water-soluble matrix, where the water-soluble matrix preferably comprises a polysaccharide polymer and a sugar alcohol, and the base typically comprises a non-water soluble matrix. The plurality of microstructures, upon penetration of the subject's skin, undergo dissolution to deliver the active agent. Also provided are related microstructure formulations, in dried and liquid form, methods for preparing the above-described microstructure arrays, and methods for administering an active agent by application of a microstructure array as provided herein to a subject's skin, among other features.