autonomic nervous system is made up of nerves that control those “automatic”
things you need to do to survive. A few of those necessary things include blood
pressure, heart rate, sweating, and digestion of your food. Autonomic
dysfunction or dysautonomia refers to problems with this autonomic nervous
What Is Autonomic
nervous system (ANS) controls several basic bodily functions. These include heart
rate, body temperature, breathing rate, digestion, and many other systems as
well. You don’t have to consciously think about these systems in order for them
to work. The ANS provides the connection between your brain and your internal
organs. For instance, it connects to the heart, liver, sweat glands, and even
the interior muscles of your eye.
The ANS is
made up of two subsystems: the sympathetic autonomic nervous system (SANS) and the
parasympathetic autonomic nervous system (PANS). Most organs have nerves from
both the sympathetic and parasympathetic systems.
usually stimulates organs. For instance, it increases heart rate and blood
pressure when necessary. The PANS, on the other hand usually slows down bodily processes.
For example, it reduces heart rate and blood pressure. There are certainly
exceptions. Digestion and urination, for instance are stimulated by the PANS
and slowed by the SANS.
responsibility of the SANS is to trigger emergency responses when required. These
“fight or flight” responses get you ready to respond to stressful situations.
The PANS, on the other hand, conserves your energy and restores tissues for
with the ANS can range from mild to life threatening. Sometimes only one part
of the nervous system is affected. In other cases, the entire ANS is affected.
Some conditions are temporary and can be reversed, while others are chronic and
will continue to worsen over time. Diseases such as diabetes or Parkinson’s
disease can cause irregularities with the ANS. Problems with ANS regulation
often involve organ failure, or the failure of the nerves to transmit a
Symptoms of Autonomic
autonomic dysfunction can include just a small part of the ANS, or the entire ANS.
Some symptoms that may indicate the presence of an autonomic nerve disorder
- dizziness and fainting upon standing
up (orthostatic hypotension)
- inability to alter heart rate with
exercise (exercise intolerance)
- sweating abnormalities, which could
alternately be too much sweat or insufficient sweat
- digestion difficulties due to slow
digestion. Resulting symptoms could include loss of appetite, bloating,
diarrhea or constipation, and difficulty swallowing.
- urinary problems. These can include difficulty
starting urination, incontinence, and incomplete emptying of the bladder
- sexual problems. In men, this could
be difficulty with ejaculation and/or maintaining an erection. In women, this
could be vaginal dryness and/or difficulty with orgasm
- vision problems. This could be blurry
vision, or the failure of the pupils to react quickly enough to changes in
Any or all
of these symptoms may be present, and effects may be mild to severe.
hypotension or orthostatic intolerance (a milder form of orthostatic
hypotension) are two of the most common conditions resulting from ANS
disorders. Orthostatic intolerance, which results in low blood pressure on
standing, causes alarming symptoms. These include lightheadedness, fainting,
and heart palpitations.
disease-like symptoms, such as tremor and muscle weakness, may also result from
certain forms of autonomic dysfunction.
Autonomic Dysfunction Conditions
types of autonomic dysfunction can be very sudden and severe, yet also reversible.
Guillain-Barre syndrome is an autoimmune disease affecting nerves of the ANS.
It has a rapid onset of symptoms, including muscle weakness, tingling, and
paralysis. However, most functions affected by this condition can be regained
of dysautonomia are conditions that can result in general autonomic failure. The
systems associated with the ANS nerves no longer work effectively when general
autonomic failure occurs. Multiple system atrophy (MSA) is a progressive
deterioration of the ANS. MSA affects all ANS-associated functions and causes
orthostatic hypotension and Parkinson’s-like symptoms. Onset is usually in
adults over 50.
primary forms of dysautonomia include:
- hereditary sensory and autonomic
neuropathies (HSAN). This is a group of related genetic disorders that cause
widespread nerve dysfunction in children and young adults. Familial
dysautonomia is in this group of diseases.
- autoimmune autonomic ganglionopathy.
This is an autoimmune disease in which the body attacks a particular set of ANS
- Holmes-Adie syndrome. This condition
mostly affects the nerves controlling the muscles of the eye, causing vision
- neutrally mediated syncope. This affects
regulation of heart rate and blood pressure, causing episodes of fainting.
dysautonomias can result from disease or damage to the body. Autonomic
neuropathy refers to damage to nerves from certain medications, injury, or
disease. Diseases causing this neuropathy include bacterial infections, alcoholism,
diabetes, and autoimmune disorders. Parkinson’s disease causes orthostatic
hypotension and other ANS failure symptoms.
Treatment of Autonomic
dysfunction is treated by addressing the symptoms of whatever form of
dysfunction you are experiencing. Orthostatic hypotension, for instance, can be
treated with lifestyle changes and medication. Symptoms can respond to
elevating the head of the bed you sleep in, drinking enough fluids, and compression
stockings to prevent blood pooling in your legs. Medications like midodrine are
also used for treating autonomic dysfunction.
underlying conditions like alcoholism, diabetes, or Parkinson’s may help
alleviate the progression of ANS dysfunction. Damage is difficult to cure. More
severe symptoms may be addressed with the help of physical therapy. Walking aides,
feeding tubes, and other methods may be used for bypassing damaged internal
Prognosis for Autonomic
the nerves of the autonomic system is often not reversible. Some illnesses like
Guillain-Barre may see significant recovery. Orthostatic hypotension responds
to treatment, but there is an increased risk of stroke due to the sudden blood
pressure changes. More general and severe conditions, such as multiple system
atrophy, might have a life expectancy of six to ten years (Mayo Clinic, 2011).