There are no published studies that have compared quality outcomes of hospitalized poisoned patients primarily under the care of physician medical toxicologists to patients treated by non-toxicologists. We hypothesized that inpatients primarily cared for by medical toxicologists would exhibit shorter lengths of stay (LOS), lower costs, and decreased mortality. Patients discharged in 2010 and 2011 from seven hospitals within the same health care system and greater metropolitan area with Medicare severity diagnosis-related groups for "poisoning and toxic effects of drugs" with and without major comorbidities or complications (917 & 918, respectively) were identified from a Premier® database. The database contained severity-weighted comparisons between expected and observed outcomes for each patient. Outcome parameters were differences between expected and observed LOS, cost, and percent mortality. These were then compared among groups of patients primarily admitted and cared for by (1) medical toxicologists at one hospital (Banner Good Samaritan Medical Center, BGS), (2) non-toxicologists at BGS, and (3) non-toxicologists at six other hospitals. Records of 3,581 patients contained complete data for assessment of at least one outcome measure. Patients cared for by medical toxicologists experienced favorable differences in LOS, costs, and mortality compared with other patient groups (p<0.001). If patients cared for by non-toxicologists had experienced similar differences in observed over expected values for LOS, cost, and mortality as those cared for by medical toxicologists, there would have been a median savings of 1,483 hospital days, $4.269 million, and a significant decrease in mortality during the 2-year study period. Differences between observed and expected LOS, cost, and mortality in patients primarily cared for by medical toxicologists were significantly better than in patients cared for by non-toxicologists, regardless of facility. These data suggest that significant reductions in patient hospital days, costs, and mortality are possible when medical toxicologists directly care for hospitalized patients.