From Richard N. Fogoros, M.D.,
Your Guide to Heart Disease.
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In the 19th and early 20th centuries there used to be a condition called neurasthenia. People would find themselves suddenly unable to function, due to a host of inexplicable symptoms, often including fatigue, weakness, strange pains, dizziness and passing out. Doctors would not find anything to explain these symptoms, so they were attributed to a "weak nervous system," or neurasthenia. Women with neurasthenia (for men were not given this diagnosis, by and large) were often confined to their beds, where they would either recover or, eventually, die. And while nobody knew what caused this condition, everyone - doctors and laymen alike - took it seriously.

Most modern doctors hearing about this mysterious condition merely shake their heads in wonder. Few seem to consider the possibility that "neurasthenia" is still with us. Consequently they are less capable of recognizing the manifestations of this condition than were their old-time counterparts, and tend to be far less sympathetic to its victims.

Yesterday's neurasthenia, today's dysautonomia

People who a century ago would have been called "neurasthenics" today are given a host of diagnoses. These include chronic fatigue syndrome (CFS,) vasovagal or neurocardiogenic syncope, panic attacks, anxiety, inappropriate sinus tachycardia (IST,) irritable bowel syndrome (IBS,) postural orthostatic tachycardia syndrome (POTS,) or fibromyalgia. Sufferers of all these conditions tend to experience an imbalance, and most often a peculiar volatility, in the autonomic nervous system - an imbalance that we now call dysautonomia.

The autonomic nervous system controls the “unconscious” bodily functions, such as heart rate, digestion, and breathing patterns. The autonomic nervous system consists of two parts: the sympathetic system and the parasympathetic system. The sympathetic system can best be thought of as controlling the “fight or flight” reactions of the body, producing the rapid heart rates, increased breathing, and increased blood flow to the muscles that are necessary when an individual is in danger or under stress. The parasympathetic system controls the “quiet” body functions, for instance, the digestive system. In short, the sympathetic system gets the body ready for action, while the parasympathetic system gets the body ready for rest. And in normal individuals, the parasympathetic and sympathetic components of the autonomic nervous systems are in perfect balance, from moment to moment, depending on the body’s instantaneous needs.

In people suffering from dysautonomia, the autonomic nervous system loses that balance, and at various times the parasympathetic or sympathetic systems inappropriately predominate. Symptoms can include frequent, vague but disturbing aches and pains, faintness (or even actual fainting spells), fatigue and inertia, severe anxiety attacks, tachycardia, hypotension, poor exercise tolerance, gastrointestinal symptoms such as irritable bowel syndrome, sweating, dizziness, blurred vision, numbness and tingling, anxiety and (quite understandably), depression.

Sufferers of dysautonomia can experience all these symptoms or just a few of them. They can experience one cluster of symptoms at one time, and another set of symptoms at other times. The symptoms are often fleeting and unpredictable, but on the other hand they can be triggered by specific situations or actions. (Some people have symptoms with exertion, for instance, or when standing up, or after ingesting certain foods.) And since people with dysautonomia are usually normal in every other way, when the doctor does a physical exam he or she often finds no abnormalities.

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