Thanks for "Caputpurge"
I want to thank all those who on and off list have responded to my query about "Caputpurge." The consensus seems to be that the preparation, mentioned by several medieval authors, consisted of a liquid of variable composition which was instilled into the nostrils with the purpose of “purging the head,” that is, of inducing nasal discharge. The name may also have been applied to a tool used in the process, probably something like a funnel. Plinio Prioreschi