OBJECTIVE: To describe the epidemiology, management, and outcome of parasuicide in the south west of England. DESIGN: Descriptive analysis using routine information systems. SETTING: The former South Western Regional Health Authority, population aged 10 and over: 2.9 million. SUBJECTS: These comprised 5080 residents of the South Western Health Region, admitted on 5770 occasions for parasuicide between April 1992 and March 1993 to hospitals in the south west. MAIN OUTCOME MEASURES: Person based age and sex standardised admission ratios for parasuicide; readmission for parasuicide in the subsequent 12 months; admission to psychiatric hospital after parasuicide; in-hospital mortality for those admitted after attempted suicide. RESULTS: The overall rate of parasuicide admission was 174 per 100,000 per year. Rates were highest in males aged 20-24 (381 per 100,000) and in females aged 15-19 (625 per 100,000). Parasuicide is the third most frequent cause of acute medical admission in the south west. A total of 10.0% of admissions received psychiatric inpatient care as a direct result of their parasuicide admission and 10.1% were readmitted in the following 12 months with a repeat episode of parasuicide. Significant variations in standardised admission ratios for parasuicide were observed between the districts. Some of this variation is related to socioeconomic differences between districts, the rest is probably due to differences in practice between districts. There is no clear evidence that these variations result in differences in readmission rates. Districts where psychiatric inpatient facilities were located on the same site as the general hospital tended to admit a greater percentage of parasuicide patients for psychiatric inpatient care. A quarter of all suicide deaths from overdose occurred in hospital. It is estimated that there are 87,000 parasuicide admissions in England and Wales annually. CONCLUSIONS: Parasuicide is a common cause of acute hospital admission and there is evidence that hospital admission practices for parasuicide vary across the south west. Randomised controlled trials are needed to evaluate the most appropriate form of management for those patients who do not require admission on medical grounds.