If you're using the spray on lube, its basically just lanolin dissolved in alcohol.
I just spray some 99% alcohol into mine to rinse it out, but I do this just before sizing the last few cases in a batch. This leaves a slight coating of lube in the die for storage between uses. I actually rinse like this a time or two while sizing a batch of casings just to prevent build up of lanolin. This is fairly convenient and alcohol (isopropyl) is cheap as dirt.