two therapies (not cures but useful): postural drainage - literally hang your upperbody upside down to boost natural drainage, either from a monkeybars or just hang forward off a table etc. if you can, get someone to play the bongoes on your back ribs to loosen snot up. 2. head out into hot dry country to breathe very dry air. thats why they used to send tb patients like doc holliday out to arizona. the russians used old salt mines to breathe in salt microdust.
Australia