Hannah is a 28-year-old single woman who presents to Dr. Ingram for an initial psychiatric appointment with a chief complaint of “I have binge eating disorder and I think I might benefit from the medication I saw on the commercial.” Hannah reports to Dr. Ingram a 15-year history of episodes of overeating (sometimes only having a second portion of food, but other times eating large quantities of food such as two boxes of cookies and a pint of ice cream). She describes feeling unable to stop until she feels “so full” she needs to vomit. She states that she does this on average once a week, though has periods where it is more or less frequent. She denies misusing laxatives or exercise for weight control. She will sometimes restrict her food intake for a couple of days in a row, eating approximately 500 calories per day, in order to “make up” for her overeating or if she is “feeling bloated.” She is 5′7″ and 130 lb, with a BMI of 20.4. She reports that her eating episodes are typically triggered by feeling angry or upset with others, such as her boyfriend, Tom.

She also reports drinking “several” alcoholic drinks three nights a week “with friends”; she is hesitant to further quantify, but admits that she does occasionally have loss of memory of events during a period of intoxication and explains this has “caused” her to do “stupid things,” such as having sexual encounters with men other than Tom, which has caused problems in their relationship. She has never tried to stop drinking and has never sought treatment for it. She reports erratic sleep patterns, with some weekends where she only sleeps 2–3 h a night, but then will have to take off a day from work the next week to sleep. She admits to having difficulty with “frustration” and will “scratch” her skin with her fingernails in response to such emotions, sometimes drawing blood. She relates one psychiatric hospitalization at age 13 after she disclosed to her school counselor that she had cut her outer forearm with a razor blade (no sutures needed) and taken 5 tablets of acetaminophen earlier that day. She believes she was given a diagnosis of “depression” at the time. She has occasionally been to therapists and psychiatrists and says she has been told she is “depressed” or “bipolar,” with past short trials of fluoxetine, sertraline, lamotrigine, topiramate, and risperidone. She never continued any of the medications for more than a few weeks, due to not feeling they were helpful or because of side effects.

When Dr. Ingram asks what Hannah hopes will be different this time in treatment, she states that she hears that the medication lisdexamfetamine (Vyvanse) can help stop binge eating disorder, and she would like to try it.

Preferred diagnosis: Alcohol Use Disorder . Bulimia nervosa .

The case of Hannah highlights the complexity of psychiatric diagnosis. Even in relatively straightforward situations, there can be uncertainty about whether adequate diagnostic criteria are met, and whether a syndrome exceeds the threshold at which it should be considered worthy of clinical attention. More challenging cases, like Hannah’s, involve numerous symptoms crossing various diagnostic categories. The clinician may be left puzzled and unclear about which aspects of the presentation and history to focus on and how to conceptualize the patient’s problems. This may result in the clinician overzealously assigning several diagnoses at once, and then potentially not knowing how to prioritize treatment; alternatively, it may lead to overlooking important symptoms or diagnostic clues because of the multitude of information, and assigning a single diagnosis, missing major areas of psychopathology that would benefit from treatment. There exists a constant tension between appropriately assigning diagnoses where criteria are met and following the law of parsimony by explaining a patient’s symptoms with as few diagnoses as possible.