Lethargy is a symptom of many illnesses...This is a symptom in which one feels extremely tired, drowsiness, lack of energy....Blood disorders can be a culprit, however , there are many other causes...If this is something that you are expiriencing, I would advise you to seek medical attention to have this evaluated......I hope this was abit helpful...Please, post again if you have further questions or concerns...Good Luck to you and God Bless.
