An apparatus is disclosed for preparing a liquid preparation using a two-part system comprising a first part including a first reagent and a second part including a second reagent, wherein the first reagent and the second reagent react when mixed to form an active ingredient of the liquid preparation. The apparatus comprising a mixing funnel having a reaction chamber, an inlet region for admitting a quantity of the first part and a quantity of the second part into the reaction chamber, for example from a dispensing capsule, to form a reagent mixture in the reaction chamber in use, and an outlet comprising at least one restriction orifice for releasing the reagent mixture from the reaction chamber at a controlled rate, and a primary chamber arranged to receive the reagent mixture from the reaction chamber through the restriction orifice.