Tiredness: a physiological state in which muscles become fatigued by the LACTIC ACID accumulating in them as the result of their activity. For the removal of lactic acid in the recovery phase of muscular contraction, oxygen is needed. If the supply of oxygen is not plentiful enough, or cannot keep pace with the work the muscle is doing, then lactic acid accumulates and fatigue results. There is also a nervous element in muscular fatigue: it is diminished by stimulation of the sympathetic nervous system. (See also MUSCLE.)
Chronic fatigue is a symptom of some illnesses such as ANAEMIA, CHRONIC FATIGUE SYNDROME (CFS), HYPOTHYROIDISM, MONONUCLEOSIS, MOTOR NEURONE DISEASE (MND), MYASTHENIA GRAVIS, MYALGIC ENCEPHALOMYELITIS (ME) and others. Some drugs may also produce a feeling of fatigue.
n. 1. mental or physical tiredness, following prolonged or intense activity. Muscle fatigue may be due to the waste products of metabolism accumulating in the muscles faster than they can be removed by the venous blood. Incorrect or inadequate food intake or disease may predispose a person to fatigue. 2. the inability of an organism, an organ, or a tissue to give a normal response to a stimulus until a certain recovery period has elapsed.
(CFS) is a recently designated semi-disease, often attributed to EBV (the Epstein-Barr virus) or CMV (Cytomegalovirus) infections, characterized by FUOs (Fevers of Unknown Origin) and resulting in the patient suffering FLS (Feels Like Shit). In most of us, the microorganisms involved in CFS usually provoke nothing more than a head cold; in some individuals, however, they induce a long, grinding, and debilitating disorder, characterized by exhaustion, depression, periodic fevers...a crazy-quilt of symptoms that frustrates both the sufferer and the sometimes skeptical physician. MCS (Multiple Chemical Sensitivities) are another syndrome that is often lumped with CFS, and they may often be two faces of the same condition. I am not using all these acronyms to mock the conditions, but as an irony. There is too much (Acronym Safety Syndrome) in medicine, reducing complex and frustrating conditions to insider’s techno-babble, somehow therein trivializing otherwise complex, painful and crazy-making problems. The widest use of acronyms (AIDS, HIV, CFS, MCS, MS etc.) seems to be for diseases hardest to treat, least responsive to procedural medicine, and most depressing to discuss with patients or survivors.... chronic fatigue syndrome
See also MYALGIC ENCEPHALOMYELITIS (ME). A condition characterised by severe, disabling mental and physical fatigue brought on by mental or physical activity and associated with a range of symptoms including muscle pain, headaches, poor sleep, disturbed moods and impaired concentration. The prevalence of the condition is between 0.2 and 2.6 per cent of the population (depending on how investigators de?ne CFS/ME). Despite the stereotype of ‘yuppie ?u’, epidemiological research has shown that the condition occurs in all socioeconomic and ethnic groups. It is commoner in women and can also occur in children.
In the 19th century CFS was called neurasthenia. In the UK, myalgic encephalomyelitis (ME) is often used, a term originally introduced to describe a speci?c outbreak such as the one at the Royal Free Hospital, London in 1955. The term is inaccurate as there is no evidence of in?ammation of the brain and spinal cord (the meaning of encephalomyelitis). Doctors prefer the term CFS, but many patients see this as derogatory, perceiving it to imply that they are merely ‘tired all the time’ rather than having a disabling illness.
The cause (or causes) are unknown, so the condition is classi?ed alongside other ‘medically unexplained syndromes’ such as IRRITABLE BOWEL SYNDROME (IBS) and multiple chemical sensitivity – all of which overlap with CFS. In many patients the illness seems to start immediately after a documented infection, such as that caused by EPSTEIN BARR VIRUS, or after viral MENINGITIS, Q FEVER and TOXOPLASMOSIS. These infections seem to be a trigger rather than a cause: mild immune activation is found in patients, but it is not known if this is cause or e?ect. The body’s endocrine system is disturbed, particularly the hypothalamopituitary-adrenal axis, and levels of cortisol are often a little lower than normal – the opposite of what is found in severe depression. Psychiatric disorder, usually depression and/or anxiety, is associated with CFS, with rates too high to be explained solely as a reaction to the disability experienced.
Because we do not know the cause, the underlying problem cannot be dealt with e?ectively and treatments are directed at the factors leading to symptoms persisting. For example, a slow increase in physical activity can help many, as can COGNITIVE BEHAVIOUR THERAPY. Too much rest can be harmful, as muscles are rapidly weakened, but aggressive attempts at coercing patients into exercising can be counter-productive as their symptoms may worsen. Outcome is in?uenced by the presence of any pre-existing psychiatric disorder and the sufferer’s beliefs about its causes and treatment. Research continues.... chronic fatigue syndrome (cfs)
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