Most people feel tired after a busy day, but bona fide medically diagnosed exhaustion is something else entirely. Exhaustion may also be described as fatigue, languidness, lassitude, listlessness, lethargy and languor. Fatigue or exhaustion symptoms are reported by the patient as opposed to being something that is observed by others, which would be a sign instead of a symptom.
It is important to know the difference among the terms tiredness, fatigue and exhaustion. Everyone has experienced tiredness at the end of a long day. Typically all it takes to recover is rest and relaxation. Fatigue and exhaustion are quite different from tiredness.
Fatigue VS. Exhaustion
Someone who suffers from fatigue has difficulty concentrating and sleeping along with a reduction in stamina and physical ability. The person may avoid social activities they used to enjoy and this can not be ameliorated with rest and relaxation. On the other hand, exhaustion is considered to be more serious.
Exhaustion symptoms include numbness, delirium, confusion and inability to stay awake or even to fall asleep. Often the person exhibits 
complete withdrawal from other people. This serious situation usually indicates a deeper problem that requires medical intervention. You will occasionally read about performers who collapsed on stage and were subsequently diagnosed with exhaustion. These celebrities include Rihanna, Lady Gaga and Madonna and most ended up in the hospital with an IV in their arm.
Medically Diagnosed Exhaustion
According to the World Health Organization, medically diagnosed exhaustion may have many causes such as overexertion, pregnancy, heat and combat. Low thyroid, cancer and other medical issues may have fatigue or exhaustion as a side effect. Many doctors believe that overwork and sleep loss lead to exhaustion that contributes to long-term health problems such as heart disease, depression and gastrointestinal problems.
Exhaustion encourages low serotonin in the body, and this is known to cause anxiety, depression and insomnia. Exhaustion symptoms may indicate serious health problems such as coronary artery disease, diabetes, thyroid gland disorders, liver disease and kidney disease.
Beware Of Misdiagnoses
Sometimes exhaustion symptoms have masked or led to a misdiagnosis of a more serious disorder. For example, hypertrophic cardiomyopathy (HCM) is a genetic condition that thickens the heart muscle and could result in a dangerous irregular heartbeat. This condition was often diagnosed as exhaustion especially among athletes.
In fact, HCM is regarded as the number one cause of sudden and unexpected cardiac death for young people. This is why it is important to look beyond the diagnosis of fatigue or exhaustion for a more serious medical condition.