Dr. Ben Wedro practices emergency medicine at Gundersen Clinic, a regional trauma center in La Crosse, Wisconsin. His background includes undergraduate and medical studies at the University of Alberta, a Family Practice internship at Queen's University in Kingston, Ontario and residency training in Emergency Medicine at the University of Oklahoma Health Sciences Center.
Dr. Charles "Pat" Davis, MD, PhD, is a board certified Emergency Medicine doctor who currently practices as a consultant and staff member for hospitals. He has a PhD in Microbiology (UT at Austin), and the MD (Univ. Texas Medical Branch, Galveston). He is a Clinical Professor (retired) in the Division of Emergency Medicine, UT Health Science Center at San Antonio, and has been the Chief of Emergency Medicine at UT Medical Branch and at UTHSCSA with over 250 publications.
Fatigue (either physical, mental or both) is a symptom that may be
difficult for the patient to describe and words like lethargic, exhausted and
tired may be used.
Taking a careful and complete history is the key to help making the
underlying diagnosis of the cause for the symptom of fatigue, However, in about
a third of patients the cause is not found and the diagnosis is not known.
There are numerous causes of fatigue symptoms. Examples of some treatable causes of
fatigue include anemia, diabetes,
thyroid disease, heart disease, COPD and sleep
Long lasting complaints of fatigue does not equate to chronic fatigue
syndrome. Specific criteria as set by the CDC need to be met to make that
Fatigue can be described as the lack of energy and motivation (both physical
and mental). This is different than drowsiness, a term that describes the need
to sleep. Often a person complains of feeling tired and it is up to the
professional to distinguish between fatigue and drowsiness, though both can occur at
the same time. Aside from drowsiness, other symptoms can be confused with
fatigue including shortness of breath with activity and muscle weakness. Again,
all these symptoms can occur at the same time. Also, fatigue can be a normal
response to physical and mental activity; in most normal individuals it is
quickly relieved (usually in hours to about a day, depending on the intensity of
the activity) by reducing the activity.
Fatigue is a very common complaint and it is important to remember that it is
a symptom and not a disease. Many illnesses can result in the complaint of
fatigue and they can be physical, psychological, or a combination of the two.
Often, the symptom of fatigue has a gradual onset and the person may not be
aware of how much energy they have lost until they try to compare their ability
to complete tasks from one time frame to another. They may presume that their
fatigue is due to aging and ignore the symptom. This may lead to a delay in
While it is true that depression and other psychiatric issues may be the
reason for fatigue, it is reasonable to make certain that there is not an
underlying physical illness that is the root cause.
Individuals with fatigue may have three primary complaints; however, it can vary in each person.
There may be lack of motivation or the ability to begin an activity;
the person tires
easily once the activity has begun; and
the person has mental fatigue or difficulty with
concentration and memory to start or complete an activity.
While fatigue can last for a prolonged period of time, the presence of
chronic fatigue is different than
chronic fatigue syndrome, which has specific
set of two criteria set for by the Centers for Disease Control and Prevention as
Have severe chronic fatigue for at least six months or longer with other
known medical conditions (whose manifestation includes fatigue) excluded by
clinical diagnosis; and
Concurrently have four or more of the following symptoms:
Fatigue is mainly a symptom and not a disease in itself. The key is
for the doctor, with the patient's help, to discover the underlying
cause of fatigue. The patient's input is important because accurate
answers to the doctor's questions may lead the doctor toward a diagnosis
or, at least, may suggest what medical tests may help provide a