To determine whether patients given prescriptions for acetaminophen-containing narcotic analgesics receive appropriate discharge instructions to reduce their intake of or stop taking other acetaminophen-containing products, we evaluated discharge instructions given by an urban, tertiary-care emergency department from September 1 to September 18, 2001 to find patients discharged while taking narcotic-analgesic compounds containing acetaminophen. We evaluated these discharge instructions to determine whether they included instructions to reduce or discontinue the use of acetaminophen compounds. Among the 1,505 discharge instructions evaluated, we found that 108 patients were discharged with a narcotic-analgesic combination product containing acetaminophen. Of these 108 patients, none of those given a prescription for such an acetaminophen-containing product was instructed to reduce or discontinue the use of other acetaminophen products. Emergency physicians, during the specified study period, did not explain to their patients the need to reduce the use of other acetaminophen-containing products when prescribing acetaminophen-containing medications. Further inquiry into this potentially dangerous activity is warranted. (Am J Emerg Med 2003;21:48-50.