Cloudy with a chance of Brain Fog

December 1st, 2017 / By Gail Barackman

Recently, I experienced a period of time when my brain felt fuzzy, or better yet, foggy. And not the kind of fogginess you suffer after a bad night’s sleep or skipping that second cup of coffee, but a persistent, all day haze marked by irritability, lack of energy and inability to focus. That week long (or longer) feeling of being among the walking dead is better known as “Brain Fog.”

Brain fog is not a diagnosis in itself, but rather a collection of symptoms. Some of the more common symptoms are an inability to focus or concentrate, memory deficit, and lack of mental clarity. Patients may also experience irritability, fatigue, low energy or mild depression.

My brain fog was preceded by a highly stressful month coupled with poor diet, lack of sleep, and very little exercise, plus I am sure my pre-existing Hashimoto’s disease did not help. Stress, lack of proper rest, and lack of exercise are common causes of brain fog, but there are many other medical problems that may contribute to the condition. Hypothyroidism, anemia, diabetes, migraine headache and depression have been known to cause brain fog, as well as many auto immune diseases such as lupus, arthritis and multiple sclerosis.

So what ICD-10 code do we report when the diagnosis is brain fog? I, using my brain fog-clouded, curious coder mind went immediately to the ICD-10-CM coding book index and looked under fog….nothing there…then brain… there’s brain death, but I am not that far gone! What’s next? Well, if there is not a code associated with brain fog, we must go with what we do have: the signs and symptoms and/or underlying disease.

If I were to code my brain fog, I would use the following codes:

  • E06.3                Hashimoto’s disease*
  • R45.4                Irritability
  • R41.0                Disorientation (haziness)
  • R53.83             Fatigue (lack of energy)
  • R41.840           Attention/concentration deficit (inability to focus)

Don’t let your coding judgment get clouded! If you are a little foggy on what code to use, it is important to remember that when there is a lack of a definitive, “codeable” diagnosis, we must rely on what we have. Code underlying conditions, and unless there is a clear connection between a disease process and the symptoms, report both the disease and the signs and symptoms codes.

Gail Barackman is a coding analyst at 3M Health Information Systems.


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