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"What is the fatigability test?"

ZocdocAnswersWhat is the fatigability test?


I have muscle fatigue that I can't explain, and I'm a 35 y/o woman in otherwise good health. I keep reading about something online called a fatigability test, but I can't find a good description of it. What is it and how does it work? Is it expensive? Is it a good place to start my treatment?


Fatigue is a difficult medical symptom, because it can be caused by many different conditions. The good news is that you say that you are otherwise in good health. Presumably, this means you have not experienced any unexplained weight loss or other symptoms which might increase the likelihood that you have a serious medical illness. The fatigability test is type of specialized nerve-muscle conduction test that is performed in certain neuromuscular specialty centers. It is most utilized in diagnosing disease of the muscle fibers themselves or the nerve-muscle junctions and how they work. For example, nerve-muscle conduction tests may be used to diagnose myasthenia gravis or muscular dystrophy. However, before jumping to this, there are many other more common cause for fatigue and for muscle fatigue. These can include some fairly benign things, such as exhaustion, overwork, and poor sleep. They may also include the effects of some medications you may be taking (such as medicines to lower your cholesterol), or certain hormonal problems, such as an imbalance of your thyroid gland. In short, the best place to start is a good physical examination and probably some basic bloodwork by your primary care doctor. From there, the decision can be made to perform more specialized tests if needed.

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