Systems, methods, and apparatuses for providing instillation therapy with a negative-pressure source are described. The apparatus can include a housing having a dosing chamber and a negative-pressure chamber fluidly isolated from each other. The apparatus can also include a moveable barrier disposed in the housing between the dosing chamber and the negative-pressure chamber. The housing includes a fluid inlet in fluid communication with the dosing chamber and a fluid outlet in fluid communication with the dosing chamber. The housing can also include a negative-pressure inlet in fluid communication with the negative-pressure chamber and a biasing element coupled to the moveable barrier. The biasing element is operable to move the moveable barrier between a charge position and a discharge position.