Hello, I would like to address your query. Would you please tell me a few details so that I can try and help you further. There are many possibilities as to why you have excessive tiredness. Are you a male or female? And how old are you? If you are female, and you are still menstruating, you could be losing too much blood or not getting enough iron in your diet. In case you are overweight, you might be having some problems breathing during your sleep, something which you might not be aware of. Hence your sleep might not be adequate even though you are sleeping 8-10 hours a day. And could you provide more details about the diet that you are taking and the kind of activity that you do? In case your diet is not healthy or too low in calories, this might leave you in a state of tiredness even though you are getting enough sleep. Excessive tiredness might be a sign of endocrine problems as well. If you are having excessive hunger and urination, or dizziness, you might want to get your blood sugar checked by a doctor. If you are having prominent muscle weakness, you might want to get your complete metabolic profile worked up by a doctor, to verify for electrolyte abnormalities. In case you have been having palpitations, excessive sweating, intolerance to hot or cold, gaining or losing weight, you might want to get your thyroid functions tested by a doctor. In case your mood is low and you feel depressed, you might want to get evaluated by a psychiatrist. I hope this helps and do provide me with some more information about other symptoms that you might be having. I might be able to give you more information regarding your ailment. Thanks, and best regards.