To improve the performance of pressurized metered dose inhalers (pMDIs) a better mechanistic understanding of early deposition within the device and upper airways is needed to move toward more efficient inhalation therapies. The present work aimed to address the longstanding gap between plume geometry (PG) measurements and pulmonary drug delivery by evaluating PG with the Plume Induction Port Evaluator (PIPE), a mass-based method that characterizes plume angles under flow and within a restricted geometry. Three Rhodamine B solution pMDI formulations containing 2.49, 9.99, and 19.99