ZocdocAnswersHow do fatigue and tiredness differ?

Question

How do fatigue and tiredness differ?

Is there a difference between fatigue and tiredness? I'm trying to figure out why I've been do run-down lately, and some medical resources use the terms interchangeably, but some don't. Is fatigue a specific condition?

Answer

Fatigue and / or tiredness are both common symptoms. While there are many simple, non-worrisome causes of these symptoms, there are also some causes that require medical attention. I encourage you to see your primary care doctor. Fatigue and tiredness are both symptoms that are very similar. They both describe an overall feeling of decreased energy. Most people will use them interchangably. Some people suggest that tiredness is the feeling of decreased energy all the time, while fatigue is when somebody develops decreased energy with less activity then expected. That is, fatigue is when one develops tiredness easier than you would expect. That being said, in the mind of the physician, either of the two symptoms will bring up the same concerns and list of possible causes (with a few rare exceptions). Common causes of fatigue and/or tiredness include: anemia (low blood count)-especially true in young women, low thyroid hormone or hypothyroidism, heart problems such as heart failure, infections, poor sleep habits, and depression. A rare cause of fatigue (as opposed to tiredness), is myasthenia gravis--when actually someone becomes generally weaker as the day progresses. Overall, the symptoms are hard to differentiate. Fatigue, tiredness, weakness, shortness of breath, fevers are all sometimes experienced in a similar fashion by patients and therefore the descriptors are less than reliable. If you have these symptoms, I encourage you to talk to your doctor.

This answer is for general informational purposes only and is not a substitute for professional medical advice.

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