As a physician and prominent hypochondriac, it is difficult to exercise some academic discipline and calmly examine the pros and cons of health concerns relating to my abyss of fatigue. I usually become less kind to myself than to my patients, so I stand in front of the mirror and give the following self-order: “Get a grip, you tired old crock. You simply need some sleep.”

When a patient visits my office and tells me he or she is always tired, I usually don’t tell the patient my opinion in this tender and caring way until I have heard their story in great detail and performed a physical examination. In most cases, the cause of fatigue emerges in the history and physical. Unlike the baseless and random suggestions in my imaginative self-assessment, the evaluation of fatigue in most physicians’ offices is an orderly process whose goal is to categorize the fatigue as acute, chronic, physiologic, functional or organic.

Fatigue, which comes on suddenly, i.e., “acutely,” usually signals the onset of a common viral illness. The body makes an anti-viral hormone called interferon which causes the short list of symptoms we all recognize as the onset of flu, i.e., muscle aches, headache, loss of appetite and, of course, fatigue.

Physiologic fatigue is found in a person’s medical history and refers to the common tired feeling that comes from overwork (mental or physical) and too little or poor-quality sleep. Fatigue caused by sleep disorders has only recently been recognized as a significant problem. Sleep disorders may be associated with snoring, obesity, lung disease, heart disease, liver disease, excessive caffeine intake, alcohol, or chronic pain, like the kind associated with arthritis. Physiologic fatigue is the body’s way of ordering you to stop burning the candle at both ends or risk going up in psychological flames. This fatigue is corrected by getting some high quality Z’s, even if a sleep specialist is needed.

My brother is a sleep specialist; he told me to go to bed! However, he and other sleep specialists have cured severe fatigue by finding and treating the specific problem impairing or preventing high quality sleep.

Functional fatigue is another common form of fatigue and is usually due to depression, anxiety or both. This form of tiredness usually is worse upon awakening, is not resolved with a good night’s sleep, may have been a problem for years, is usually constant in severity over time, and is unrelated to work or exercise. It is frequently brought about by worry, stress, major life changes, or difficult events such as the death of a loved one. If you tell your physician about your fatigue, also tell him about what’s happening in your life. The good news is that anxiety and depression can be well treated with medications.

Chronic fatigue may be a manifestation of a significant medical problem, especially if the fatigue has lasted for several months, becomes progressively more severe over time, and tends to be worse as the day progresses. Disorders such as viral hepatitis, mononucleosis, heart disease, anemia and many kinds of cancer cause chronic fatigue. A physical exam will point the way to arrive at a diagnosis. Many common drugs – antihistamines, tranquilizers, and blood pressure medicines – can also cause fatigue.

Then, there’s the specific disorder called chronic fatigue syndrome. CFS is diagnosed when, in addition to specific criteria, the patient is seriously impaired in activities of daily living. CFS may have features of a post-viral infectious disorder and of major depression, but it is more complex than either of these. CFS is the most difficult of the fatigue-associated disorders to define and treat, but progress has been made in the past decade.

Fatigue is a very common problem. If fatigue is brief, it’s likely due to a virus. If recurrent or progressive, fatigue should be brought to your family physician’s attention. If you are like me, get some rest, and then “Up and at ‘em” once again to conquer the world – and my imagination.

Good Night.