Costs of management of irritable bowel syndrome (IBS) are unknown. The direct medical charges in community subjects with IBS were estimated. An age- and sex-stratified random sample of residents of Olmsted County, Minnesota, ranging in age from 20 to 95 years, was mailed a valid self-report questionnaire. Subjects were categorized as having IBS, having some symptoms but inadequate criteria for IBS, and controls. All charges (in 1992 U.S. dollars) for health services rendered in the year before completing the survey were obtained (except outpatient medications). A total of 88% of subjects with IBS, 86% of subjects with some symptoms of IBS, and 83% of controls incurred direct medical charges during the study year. The odds of incurring charges were 1.6 times greater in subjects with IBS relative to those without symptoms (P < 0.01) adjusting for age, sex, education, marital status, and employment. Overall median charges incurred by subjects with IBS were $742 compared with $429 for controls and $614 for subjects with some symptoms. Among those subjects with nonzero charges, there were significant positive associations with age, higher education, and symptom groups (all P < 0.01) but not sex. The economic impact of IBS is significant. A better understanding of the determinants of these costs is needed so that cost-saving strategies can be implemented.