A 73-year-old woman with multiple myeloma experienced four episodes of loss of consciousness, convulsions and profuse sweating whilst she was in the hospital. A thorough investigation in the department of medicine disclosed that with each attack, she had a serum glucose < 1.6 mM L-1, insulin level > 1400 pMol L-1 (N- < 150) and a normal level of serum C-peptide. Since she had no anti-insulin antibodies (which may rarely exist in multiple myeloma), a diagnosis of exogenous injection of insulin was made. A search for a possible perpetrator discovered that the patient had a daughter who was a surgical nurse and who was genuinely concerned whenever she was told that her mother was about to be discharged from the hospital. If she was the perpetrator in the present case, then it is possible that the motive for such an action was to postpone the mother's discharge from hospital. This case is an example of a 'factitious disease by proxy' in an elderly patient. The aim of the present report is to alert the medical personnel to the possibility that Munchausen's syndrome by proxy may also occur in the elderly.