Autonomic Nervous System Imbalance

When the body’s automatic control system stops working properly, it can affect everything from your heartbeat to your digestion, creating symptoms that may seem unconnected but stem from a single underlying problem.

Table of contents

• What Is Autonomic Nervous System Imbalance?
• Other Names
• How the Autonomic Nervous System Works
• Symptoms
• Causes
• How Common Is It?
• Diagnosis
• Treatment and Management
• Outlook

What Is Autonomic Nervous System Imbalance?

Dysautonomia, Autonomic dysfunction, Autonomic neuropathy, Autonomic failure

Autonomic nervous system imbalance is a general term for disorders that disrupt your autonomic nervous system (ANS). The ANS is a subdivision of your nervous system that manages all of your body processes you don’t think about. The term “autonomic” means “self-governing,” and the ANS controls your blood pressure, body temperature, breathing, digestion, heart rate, sweating, and much more^[1].

When you have autonomic nervous system imbalance, one or more of these automatic processes aren’t working as they should^[1]. This condition is not a single diagnosis but rather an umbrella term to describe autonomic disorders^[9]. It can range from mild to severe, and diagnosing and treating it is sometimes difficult because the condition can vary widely and take many forms^[1].

Other Names

Healthcare providers may use several different names when referring to autonomic nervous system imbalance. The most common alternative terms include dysautonomia, autonomic dysfunction, and autonomic neuropathy^[1][5].

How the Autonomic Nervous System Works

Your autonomic nervous system is a network of nerves throughout your body that control unconscious processes. These are things that happen without you thinking about them, such as breathing and your heart beating^[2]. Your ANS is always active, even when you’re asleep, and it’s key to your continued survival.

The autonomic nervous system breaks down into three divisions, each with its own job^[2]:

• Sympathetic nervous system: This system activates body processes that help you in times of need, especially times of stress or danger. This system is responsible for your body’s “fight-or-flight” response.
• Parasympathetic nervous system: This part does the opposite of your sympathetic nervous system. This system is responsible for the “rest-and-digest” body processes.
• Enteric nervous system: This part manages how your body digests food.

The ANS is responsible for maintaining homeostasis, or equilibrium, in the body. When there is a dysfunction or failure of the autonomic nervous system, the result is a disorder classified as a type of autonomic nervous system imbalance^[9].

Your autonomic nervous system manages the automatic functions of various organs throughout your body. It controls your eyes (pupil width and focus), tear production, salivation, sweating, hair follicles, heart and circulatory system, immune system, lungs, skin, and various internal organs^[2].

Symptoms

Symptoms of autonomic nervous system imbalance can affect many body systems, and they may look different depending on the system they affect^[1]. The symptoms experienced by patients vary based on the type of autonomic dysfunction and where the dysfunction is occurring within the body^[9].

The seven most common symptoms include^[9]:

• Fatigue
• Brain fog
• Lightheadedness (especially when standing up)
• Body temperature problems
• Difficulty with upright posture
• Heart palpitations
• Gastrointestinal issues

Additional symptoms may include^[1][4]:

• Balance problems and vertigo
• Fainting or passing out
• Nausea and vomiting
• Forgetfulness or trouble focusing
• Fast heart rate (tachycardia) or slow heart rate (bradycardia)
• Irregular heart rhythm (arrhythmia)
• Changes in eye pupils (pinpoint or unusually wide)
• Changes in bowel movements (constipation or diarrhea)
• Sexual dysfunction
• Chest pain or discomfort
• Frequent urge to urinate or urinary incontinence
• Shortness of breath
• Clammy or pale skin
• Sleeping problems
• Trouble swallowing
• Sound or light sensitivity
• Dizziness or lightheadedness
• Low blood sugar
• Sweating more or less than usual, or sweating more in certain body parts
• Unusually dry or watery eyes
• Migraines or frequent headaches
• Swings in body or skin temperature
• Excessive drooling
• Mood swings or anxiety
• Vision issues (blurred vision or trouble with eyes adjusting to light changes)
• Exercise intolerance (heart rate doesn’t change with physical activity)
• Runny nose

One common sign of autonomic dysfunction is orthostatic intolerance, which means difficulty maintaining upright posture. This involves abnormal blood pressure and heart rate. Patients with orthostatic intolerance present with feelings of lightheadedness, dizziness, and brain fog. It’s caused by a loss of blood flow to the brain, heart, and lungs^[9].

Another symptom of orthostatic intolerance when standing upright is an annoying pain in the back of the neck and shoulders. Because of the distribution of the discomfort, this is sometimes referred to as the “coat hanger sign.” The exact mechanism of this phenomenon is unknown, but one theory suggests it is a kind of cramp caused when the muscles holding up the head receive too little blood flow^[9].

Causes

There are two main types of autonomic nervous system imbalance, primary and secondary^[1]:

• Primary: It happens on its own without another cause.
• Secondary: It happens because of another condition.

Primary types happen on their own, without a specific cause. They aren’t as common as secondary types (where something else is causing it). A specific example of a primary type is an inherited form called familial dysautonomia. Any of the following can increase your odds of having it: being of Jewish (especially Ashkenazi Jewish) heritage, being of Eastern European heritage, or having a family member with the condition^[1].

Secondary autonomic nervous system imbalance occurs because of another condition^[1]. The most common cause is diabetes^[4][18]. Other conditions that can cause secondary autonomic dysfunction include:

• Parkinson’s disease
• Multiple sclerosis
• Stroke
• Cancer
• Amyloidosis
• Autoimmune diseases
• Alcohol abuse
• Viral or bacterial infections
• Certain medications
• Toxic exposures
• Tumors

How Common Is It?

Various forms of autonomic nervous system imbalance are relatively common. More than 70 million people worldwide have some form of it^[1][9]. It can be congenital (meaning it’s something you have at birth), or you can develop it at any point in life. The average time of onset is between the ages of 50 and 60^[1].

Often, autonomic nervous system imbalance presents as an invisible illness. Patients may not look sick, and yet they have symptoms that make it difficult to work, go to school, and perform activities of daily living^[9].

Autonomic nervous system imbalance is often something that healthcare providers have limited experience with because the condition can vary widely and take many forms. It is often a complicated condition to detect, diagnose, and treat^[1].

Diagnosis

Autonomic nervous system dysfunction is sometimes challenging to diagnose because of its many different types of symptoms. These symptoms often overlap with other conditions. As a result, you may need to see a multidisciplinary team of providers to fully evaluate your symptoms and help exclude any non-neurological problems^[6].

If you have symptoms of autonomic nervous system imbalance but no risk factors, the diagnosis can be more involved. Your healthcare provider will probably review your medical history, discuss your symptoms, and do a physical exam^[11].

Your provider might recommend tests to evaluate autonomic functions, including^[11]:

• Autonomic function tests: These tests measure how your heart rate and blood pressure respond during exercises such as deep breathing and forcefully breathing out (Valsalva maneuver).
• Tilt-table test: This test monitors the response of blood pressure and heart rate to changes in posture and position. You lie flat on a table, which is then tilted to raise the upper part of your body.
• Blood pressure monitoring: A simpler test involves checking your blood pressure when lying, sitting, and standing.
• Gastrointestinal tests: These may be used to evaluate digestive function.

If you have known risk factors for autonomic neuropathy, such as diabetes or another condition that increases your risk, and have symptoms, your healthcare provider will perform a physical exam and ask about your symptoms^[11].

Treatment and Management

The treatment for autonomic nervous system imbalance involves managing the underlying cause of the condition and addressing the specific symptoms experienced by the individual^[15]. The goal of treatment is to improve symptoms and quality of life^[1].

Lifestyle Changes

Several lifestyle modifications can help manage symptoms. These changes are often the first line of treatment and can be very effective^[19]:

• Increasing fluid and salt intake to help maintain blood pressure
• Making dietary adjustments, such as eating smaller, more frequent meals to help with digestive issues
• Elevating the head of the bed to help with blood pressure regulation
• Wearing compression stockings to improve blood flow
• Avoiding triggers that worsen symptoms, such as prolonged standing or hot environments
• Regular, appropriate exercise as tolerated
• Stress management techniques

Medications

Doctors may recommend medications to help manage symptoms. The specific medications depend on which symptoms are most problematic^[13][15]. These may include:

• Medications to help raise blood pressure
• Medications to help regulate heart rate
• Medications to help with digestive symptoms
• Medications to help with bladder control

Other Treatments

In some cases, healthcare providers may recommend additional therapies^[15]:

• Physical therapy to help improve strength and mobility
• Supplements to address specific deficiencies
• Alternative therapies, when appropriate

Some patients might continue to receive care from a neurologist in the short-term, but the goal is often to help your primary care provider manage and coordinate your care long-term^[6].

Outlook

The outlook for people with autonomic nervous system imbalance varies widely depending on the underlying cause and severity of the condition. Some types are temporary and reversible, while others are chronic and may continue to worsen over time^[7].

When autonomic nervous system imbalance is caused by an underlying disease that can be treated, some autonomic nervous system disorders get better when that underlying disease is treated. Often, however, there is no cure. In that case, the goal of treatment is to improve symptoms^[5].

For conditions like diabetes-related autonomic dysfunction, management should focus on glucose control to prevent developing or worsening autonomic symptoms^[18].

Many people with autonomic nervous system imbalance find that their symptoms are manageable with appropriate treatment and lifestyle changes. Working closely with healthcare providers to develop an individualized treatment plan is important for improving quality of life and managing this complex condition.