A dispensing device which disperses medicate through a needle across a zone within a body with zero pressure differential. The device includes a needle which is, during use, becomes encapsulated within a tubular needle-receiving member, a therapeutic agent reservoir in fluid communication with the needle, positioned within said housing, and in communication with the needle, a second reservoir, a reservoir-connecting conduit in communication with the therapeutic agent reservoir, a fluid drive in communication with the fluid in the second reservoir and in communication with said reservoir-connecting conduit, and a linear drive attached to said needle or to said needle-receiving member.