Background Spacers are commonly used add-on devices for pressurised meter dose inhalers (pMDI) to improve drug delivery to the lungs. Plastic spacers need to be ‘prepared’ prior to use by priming or washing in order to remove possible electrostatic charge. Aim: The study aimed to evaluate the performance of a Volumatic® spacer (GSK) using two types of preparation techniques (primed with multiple actuations without prior washing and, washed with liquid detergent and used without priming) and its effects on the dose available for inhalation following administration of multiple doses of a suspension pMDI formulation. Experimental Method: The Volumatic® spacer was tested in three different conditions: new and untreated, washed, and primed. In each condition, twelve doses of salbutamol sulphate pMDI (Ventolin®, GSK) were actuated into the spacer and the emitted doses were collected and chemically quantified. Results: Data showed higher average dose of 25.11± 2.92 µg for primed condition, 16.22± 2.72 µg washed and 11.69 ± 1.12 µg new and untreated condition, respectively. Conclusion: This study showed that priming a spacer with multiple doses prior to use results in a higher exiting particle mass, indicating that priming a large-volume spacer could be advantageous in a clinical setting, where multiple doses need to be administered to patients.