Abstract: A particulate therapeutic agent delivery device and method are disclosed. In an embodiment of the device there is a respiratory-gas channel having a patient end to which a patient may be pneumatically connected, a particulate-therapeutic-agent channel in pneumatic communication with the respiratory-gas channel, a scrubber housing in pneumatic communication with the respiratory-gas channel, the scrubber housing having an expired-gas orifice for receiving expired gas from the respiratory-gas-channel, and a scrubber material situated within the housing so as to receive expired gas via the expired-gas orifice and remove carbon dioxide from the expired gas to provide treated gas, and situated so as to provide the treated gas to the respiratory-gas channel.