Dry Powder Inhaler
The DPI is different from the MDI because their is no propellant or liquid excipient contained within the DPI. The API ( active pharmaceutical ingredient ) is bound with a carrier like lactose and placed inside of a gel capsule. The gel cap is placed inside of the plastic DPI actuator, the gel cap gets pierced and as the patient inhales thru the DPI, the API is released into the stream of air traveling into the lungs.
If formulated correctly, the DPI has a bioavailability rating of 95%.
The manufacturing process to build the DPI is rather simple, with only 3 pieces of equipment needed. A blender, grinder and a capsule filler is all that is needed as far as equipment is needed.