Multi-dose dry powder inhaler (M-DPI) is a unique inhaler device from Teva Pharmaceutical developed for treatment of chronic respiratory diseases. It is a metered-dose dry powder inhaler system designed to appear as a typical pressurized metered-dose inhaler, but its internal geometry is very unique. The formulation of the inhaled corticosteroid and long-acting β2 agonist in M-DPI has been approved for use in the United States (US) [RespiClick®] and European Union (EU) [Spiromax®] as a treatment for asthma and chronic obstructive pulmonary disease (COPD). This M-DPI is easy to handle and does not need coordination between dose actuation and inhalation. The unique design of M-DPI ensures patients receive consistent doses of the drug with each actuation. The present article is a comprehensive account of the M-DPI with special emphasis on its dose metering system, deagglomeration mechanism and clinical outcomes.