How asthma inhalers are made
The valve that meters each puff of an inhaler was first designed for dispensing perfume.
- stations
- 6
- things upstream
- 42
- raw sources
- 16
- steps from the ground
- 7
The short version
A metered-dose inhaler has three parts: a canister of aluminum or stainless steel formed by deep drawing, a metering valve, and a plastic actuator. The canister is filled with the drug dissolved or suspended in a liquefied gas propellant, sealed with the valve, and fitted with the mouthpiece. Each press releases one dose.
-
Draw the canister
The canister is produced in aluminum or stainless steel by deep drawing, in which a flat blank is pressed into a cup shape without a weld.
Goes in -
Coat the surfaces
A coating on the canister and valve stops the drug from sticking to the walls. One method is gas plasma processing in a vacuum, which extends shelf life.
-
Prepare the formulation
The drug is dissolved or suspended in a liquefied gas propellant, now usually a hydrofluoroalkane. The propellant makes up over 99 percent of the delivered dose, so its properties matter more than any other single factor.
Goes in -
Fill and crimp the valve
The formulation goes into the canister and a metering valve is sealed on. The valve lets out a set quantity each time it is pressed.
-
Fit the actuator
A mouthpiece actuator is fitted, along with a dose counter in many designs. The actuator directs the aerosol toward the lungs.
Goes in -
Test the doses
Inhalers are tested to confirm each puff delivers the right amount of medicine and a mist of tiny particles.
Worth repeating
- Metered-dose inhalers were first developed in 1955 by Riker Laboratories.
- The Meshburg metering valve at the heart of the first inhaler was originally designed for dispensing perfume.
- Replacing CFC propellants with hydrofluoroalkanes in the 1990s forced a redesign, and for one steroid inhaler the smaller particles raised potency by a factor of 2.6.
Back to the ground
Follow every input upstream and asthma inhaler starts as these 16 raw sources.
Everything it is made of See it on the map
Open the whole family tree
Keep walking
Sources
Cite this page: "How asthma inhalers are made." Assembly Line, 2026-11-03. https://assemblyline.org/make/asthma-inhaler