This study investigated the number, timing and disposal (admission or discharge) of patients repeating an overdose who attended the accident and emergency department of a district general hospital during a 5-year period. There was a total of 1958 overdoses by 1597 individuals over the 5-year period. Overdoses were repeated by 12% (n = 191) of patients and accounted for 552 of the total overdoses (representing 361 repeats). First repeats were found to occur more frequently in the 3 months following the original overdose for 43% of patients, 70% of repetitions occurring within a year. The distribution of first repeats showed a similar pattern for males and females. During the 5-year period 49% of all repetitions occurred within 3 months. Almost one-fifth of repeaters were discharged, irrespective of whether it was the patient's 'index' (first overdose within the study period) or a repeat overdose. Within the repeater population, 31% of overdoses occurred on a Friday, Saturday and on, or immediately prior to, a Bank Holiday. Since there was no on-site psychiatric service available at such times, those patients had to wait until the next working day for assessment. The study recommends that all overdose patients should receive psychiatric assessment, and therefore on-site psychiatric services should be available for accident and emergency patients.