Just what is normal? And what are normal body functions? Do we all react to external factors the same, even sweat the same? When we stray from normality, whether it is the way we interact with others or raise our children, it is known as dysfunction, i.e, abnormal or impaired functioning. The human body and the systems that allow it to function may also become abnormal or impaired.

The body’s autonomous nervous system (ANS), which is essentially automatic when functioning properly, controls or regulates a multitude of functions like digestion, heart rate, breathing, body temperature, blood pressure, the dilation of your pupils and bodily functions that operate without your conscious control.

The autonomous nervous system, which is comprised of both the sympathetic (SANS) and parasympathetic autonomic nervous systems (PANS), controls dozens of bodily functions in response to external environmental factors. Aside from those already mentioned, it regulates weight gain or loss via metabolism, as well as blood flow and production of all bodily fluids, including saliva, sweat and even sexual response.

When there is damage to the nerves of the ANS, autonomic dysfunction ensues and certain bodily functions may be slowed, stimulated, sped up, stalled or shut down altogether.

Obviously, all kinds of bad things can occur with autonomic dysfunction, ranging from mild to life threatening, but we’re going to concentrate on one treatable condition in particular…

—Orthostatic Hypotension—

When you are feeling dizzy or lightheaded, it could be due to orthostatic intolerance, a symptom of orthostatic hypotension and the result of an improperly regulated ANS.  It is derived from orthostatis, which means maintaining an upright standing posture, and low blood pressure or hypotension. Changing body positions that results in the aforementioned dizziness or feeling faint, possibly fainting altogether, feeling nauseated or perspiring excessively, are warning signs of orthostatic hypotension that should be taken seriously.

Causes and symptoms of orthostatic hypotension:

You may be standing from a seated position when you experience the key symptom, a sudden drop in blood pressure. This results in some of the aforementioned symptoms— possibly others like heart palpitations, blurred vision and a feeling of instability or weakness. Even more unsettling might be subsequent chest pain, incontinence or impotence. These symptoms likely occur while performing normal daily movements and activities.


One condition that has been shown to trigger orthostatic hypotension is dehydration. Prolonged exposure to the sun, a common cause of dehydration, could be the culprit, as could immoderate exercise leading to weakness or dizziness. Other factors that might decrease blood volume and lead to dehydration are diarrhea, vomiting or bleeding.

Older People More Vulnerable…

Advanced age seems to increase vulnerability to orthostatic hypotension, with the older among us more susceptible to symptoms associated with this condition. These symptoms of dizziness and lightheadedness in this age group seems to occur frequently after meals.

Heart and Other Health Issues… 

Other medical causes shown to lead to orthostatic hypotension-induced dizziness due to autonomic dysfunction include heart ailments, diabetes, Parkinson’s disease and disorders of the endocrine and nervous systems.  These are among the medical conditions that may have instigated damage to the autonomous nervous system.

Note: The Valsalva maneuver, used by some physicians to regulate heart rate or diagnose ANS issues, namely dizziness, can actually cause dizziness, a symptom of orthostatic hypotension. It is a moderately forceful exhalation against a closed airway that may be used purposely during a bowel movement or unintentionally.