This article presents a reassessment of the evidence provided by the extant medieval Irish medical manuscripts for ritualized healing charms, focusing on a group of blood-staunching incantations preserved in a substantial, but hitherto largely unstudied, medical remedy book written primarily by the sixteenth-century Irish medical scribe Conla Mac an Leagha (fl. 1496–1509). It is argued that some of the charms in question may have been composed in the early medieval period, and reflect currents of intellectual exchange between ecclesiastical centers in Ireland and southern England, especially Canterbury, prior to the twelfth century. The apparently obscure lexical items in one of these blood-staunching charms may point to the participation of Irish literati in broader European trends relating to esoteric writing and “hermeneutic” vocabulary, and to its potential for articulating the concerns of the educated elite regarding the perceived exclusivity of literate knowledge.