Thank you so much for providing me with further details.
Fatigue and loss or lack of energy is a relatively common disorder and most often it is caused by nutritional deficiencies, which mostly include deficiency of certain essential vitamins like vitamin B 12, folic acid, vitamin A etc. This can be assessed by getting a blood work for detecting vitamins done by a laboratory and if there is a deficiency of vitamins found, then that particular vitamin can be replaced by using supplements available in the pharmacy and selecting an appropriate diet rich in the vitamin required.
Other causes of feeling a lack of energy and fatigue include disturbed sleep, such as encountered in Sleep apnoea which is a common finding in over weight or obese people. This can be detected by sleep studies, which requires monitoring of special vital signs and parameters while a person is asleep.
Anemia -- is also a cause of fatigue and lack of energy and it can be found out by a simple test known as the Complete Blood Picture (CBC), if anemic, the cause of anemia is established and eliminated and supplements can be used to raise the blood cell number to the required range.
Certain hormonal disorders like Hypothyroidism (an under active thyroid) can also cause a lack of energy along with loss of appetite and an increase in weight. This can be found out by doing Thyroid Function tests.
Other conditions can be ruled out on subsequent examination and further lab work up, these conditions can include chronic infections, malignant conditions, autoimmune disease etc.
I would suggest that you pay a visit to your Primary Physician, so that the required work up can be done and the treatment be given according to the underlying cause found.
Hope this helps.
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