The assessment of individuals who may have bulimia nervosa is similar to that described for anorexia nervosa. The patient should be asked to describe a typical day’s food intake and a typical binge and the interviewer should assess whether the patient does indeed consume an unusually large amount of food as required by the DSM-IV definition of a binge. The interviewer should explicitly inquire about self-induced vomiting and whether syrup of ipe-cac is ever used to promote vomiting. The interviewer should ask about the use of laxatives, diuretics, diet pills and enemas. A weight history should be obtained, so the interviewer can de-termine whether the binge-eating was preceded by obesity or by anorexia nervosa, as is often the case. Because there is substantial comorbidity, the interviewer should ascertain whether there is a history of anxiety or mood disturbance or of substance abuse.
The patient should be weighed and the presence of dental erosion noted. Routine laboratory testing reveals an abnormality of fluid and electrolyte balance such as those described in the section on pathophysiology in about 10% of patients with bulimia nervosa.
Probably the greatest difference in presentation is between those individuals who purge and those who do not. Individuals with the nonpurging form of bulimia nervosa are more likely to be over-weight at the time of presentation and to exhibit less general psy-chiatric illness compared with individuals who induce vomiting.