OBJECTIVE To determine the functional and cognitive outcomes of patients with prolonged refractory status epilepticus (PRSE) lasting 7 or more days despite the use of anesthetic agents for seizure suppression. METHODS Retrospective analysis. METHODS St Mary's Hospital, Mayo Clinic, Rochester, Minnesota. METHODS Fourteen patients with PRSE. METHODS Hospital follow-up interview. METHODS Survival rate of PRSE and functional and cognitive outcome of surviving patients based on the modified Rankin Scale (mRS) and Telephone Interview for Cognitive Status (TICS). RESULTS Forty-three percent of patients (6 of 14) died during hospitalization for PRSE, and 57% (8 of 14) had died by the last follow-up. Of the 6 surviving patients, 4 showed improvement and 2 showed no change in mRS score (median mRS change, -1; range, 0 to -3). Owing to preexisting cognitive deficits, 1 patient could not complete the TICS. The 5 remaining patients scored a median of 34 on the TICS (range, 30-37; reference TICS score, >or=31; maximum TICS score, 41). Age, sex, PRSE duration, and etiology were not associated with chance of survival. CONCLUSIONS Despite the high mortality rate, survival with meaningful functional and cognitive recovery is possible after PRSE. Prolonged duration of status epilepticus alone should not be considered a reason to discontinue treatment.