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"What causes one to constantly feel tired?"

ZocdocAnswersWhat causes one to constantly feel tired?


Why am I tired all the time? Sometimes I feel like it must be a disease, because I just can't get out of bed in the morning. But then, if I can drag myself out and go on a bike ride, I do feel a lot better. So is there something wrong with me, or do I just lack discipline?


There could be a lot of different reasons for this lack of energy that you are experiencing. The complete differential diagnosis is beyond the scope of this discussion, but some of the important ones to watch for will be described here. It is very important that you discuss these concerns with your primary care doctor who will be better able to evaluate your medical history and presenting symptoms and decide upon the appropriate medical work up. They may recommend your for further lab tests or imaging studies, or refer you to a specialist for further work up. They may decide upon a treatment regimen depending on whether they believe this is medically appropriate. In terms of some of the important things to be concerned about, there are disorders of the thyroid gland that can cause you to feel tired constantly. Mood disorders, such as depression, can cause you to feel tired or apathetic, and lack the energy to do the things that you normally would do. There are a variety of metabolic issues that you may be experiencing that could also explain these symptoms. Of course, as discussed, it is best for you to be evaluated by your primary care doctor for further work up.

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