A device for withdrawing or delivering a substance through the skin of a patient includes a body and a skin penetrating device having a plurality of skin penetrating members, such microneedles. The body includes a bottom surface having a first inner surface area supporting the skin penetrating members and a second outer surface having an adhesive for attaching the device to the skin. In one embodiment, the firs inner surface is spaced outwardly from the second outer surface when the device is attached to the skin. The inner surface can have a textured visually wettable surface, such as an etched surface, to provide a visual indication of leakage from the interface between the skin penetrating members and the skin.
