In psychiatry, as in the rest of medicine, it is important to distinguish between symptoms and the underlying cause of those symptoms—the diagnosis. If the focus is only on symptoms, treatment may prove insufficient or completely ineffective.

Choosing treatment based on a diagnosis, however, allows us to address not only the symptoms, but their underlying cause. Time and again, I am surprised to see patients taking medications—sometimes several medications—who have never been given a clear diagnosis, just a list of symptoms. That sloppiness can lead to poor results. Psychiatry should be no different from the rest of medicine in this regard.

Here’s a common example: Symptom = inattention. Diagnosis = ?

We often think of significant inattention as evidence of ADHD. Sometimes it is. But inattention is a symptom, not a diagnosis. Someone with a significant mood or anxiety disorder may also have considerable difficulty with attention and concentration. In those cases, once the underlying mood or anxiety disorder is successfully treated, the problems with attention will often improve as well.

Another example: Symptom = insomnia. Diagnosis = ?

Insomnia can be part of many different diagnoses, and while it is important to treat it, the most effective treatment will vary considerably depending on its cause. Is it a medication side effect? Is it related to anxiety and stress? Is it part of a more significant mood disorder, such as bipolar disorder? Teasing out these details is critical to getting the symptom—as well as its underlying cause—properly treated.

Symptoms are important, but they are the beginning of the diagnostic process, not the end of it. Understanding what is causing a symptom is what allows us to choose a treatment that has the best chance of actually helping.