We describe our early experience with use in emergency department settings of a standards-based medication history service integrated into a health information exchange (HIE). The service sends queries from one Exchange's emergency department interface both to a local ambulatory care system and to the medication hub services provided by a second HIE. This second HIE in turn sends requests to SureScripts and returns histories for incorporation into the first Exchange's clinical interface. The service caches all requests to avoid costly duplicate query charges and maintains an account of queries, registered users, charges, and results obtained. Usage may be increasing as additional retail pharmacy data become available. Early results suggest that research and development emphasis requirements will of necessity shift from obtaining prescription medication history to finding new means to ensuring effective use.