An apparatus for delivering a treatment agent includes a hand actuated pneumatic atomizer (1) that has a 7 ml generally cylindrical reservoir (2) for containing a bulk liquid that includes a predetermined concentration of the treatment agent. The bulk liquid includes a solvent in the form of water and a treatment agent in the form of hyaluric acid. The treatment agent is intended for delivery into human skin (3). Atomizer (1) includes a finger actuated pump (4) for creating a flow of droplets including the treatment agent. It will be appreciated that this flow is drawn from the bulk liquid in reservoir (2) in a sequence of doses and is supplied sequentially to a nozzle (5) for directing the flow (6) to a surface (7) of the skin (3).
