One sees universal advice to discard prescription drugs past their
expiration dates. Some drugs are expensive enough that one hesitates
to follow this sage advice without further information. We know, for
example, that careful storage reportedly practiced by the US Army
has shown that a drug with an expriation date of two or three years
may still be at rated potency for up to ten years.

I have tried, in vain, to find research data on Combivent inhalers.
Does anyone know whether there is data on potency vs. storage
times under ideal storage conditions [dry, cool]?

If not, where would one prod to obtain such data? Drug manufacturers
do not seem to invite such enquiries [grin].

Surely there must be some curiosity out there on this topic?