Dysautonomia (or autonomic dysfunction) is any disease or malfunction of the autonomic nervous system (ANS). The autonomic nervous system controls a number of functions in the body, such as heart rate, blood pressure, digestive tract peristalsis, and sweating, amongst others. Dysfunction of the ANS can involve any of these functions.
A number of conditions are forms of dysautonomia: postural orthostatic tachycardia syndrome (POTS), inappropriate sinus tachycardia (IST), vasovagal syncope, pure autonomic failure, neurocardiogenic syncope (NCS), neurally mediated hypotension (NMH), orthostatic hypotension, orthostatic hypertension, autonomic instability, and a number of lesser-known disorders such as cerebral salt-wasting syndrome. Dysautonomia may occur as the result of other diseases, such as diabetes mellitus, multiple system atrophy (Shy-Drager syndrome), Guillain-Barré syndrome and a number of other conditions that may affect the nervous system.
The symptoms of dysautonomia are numerous and vary widely from person to person. Since dysautonomia is a full-body condition, a large number of symptoms may be present that can greatly alter a person’s quality of life. Each patient with dysautonomia is different—some are affected only mildly, while others are left completely bed-ridden and disabled.
- Excessive fatigue
- Excessive thirst (polydipsia)
- Lightheadedness, dizziness or vertigo
- Feelings of anxiety or panic (not mentally induced)
- Rapid heart rate or slow heart rate
- Orthostatic hypotension, sometimes resulting in syncope (fainting)
- Gastroparesis (delayed gastric emptying)
- Mydriasis (abnormal dilation of the pupils)
- Salt cravings
- Pallor (unhealthy pale appearance)
- Acid reflux
- Visual disturbances
- Orthostatic hypotension
- Nerve pain
- Trouble breathing
- Chest pains
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In some cases, a cardiac ablation procedure can be performed to stop the heart symptoms completely. It is not recommended in POTS patients, and can in fact worsen tachycardia. Medications are also used to stabilize the condition on a long-term basis. Benzodiazepines can be used for some of the physical problems such as anxiety. In many cases treatment of primary dysautonomia is symptomatic and supportive.
Measures to combat orthostatic intolerance include:
- elevation of the head of the bed
- frequent small meals
- a high-salt diet
- fluid intake
- compression stockings
Drugs such as:
- SSRIs can also be used to treat symptoms
Treating dysautonomia can be difficult and usually requires a combination of drug therapies.