Definition: What is Vagus Nerve Dysfunction?
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Vagus nerve is one of the 12 cranial nerves in the body. These nerves come in pairs and are responsible for linking the brain to other major areas of the body such as the head and torso. Whilst some cranial nerves are responsible for transmitting sensory details such as sights, smells, sounds, and tastes (sensory functions), others control specific glands as well as muscular movement (motor functions). Whilst some nerves pertain to one type of function, the vagus nerve remains one of the major cranial nerves in the body and so it has both functions.
The vagus nerve is the longest cranial nerve within the body, as it runs all the way through the body from the brain to the stomach. Its role is to slow cardiac activity when it is excited. Over stimulation causes vagus nerve dysfunction. The heart pumps less blood into the arteries, causing the brain to become less oxygenated, as well as a sudden drop in blood pressure.
In most cases, vagus nerve dysfunction does not present immediate complications. If fainting spells are lengthy, this is known as syncope.
Symptoms of Vagus Nerve Dysfunction
Before unconsciousness sets in, there are some signs of vagus nerve dysfunction:
- feeling of weakness
- hot flashes
- vertigo
- blurred vision
- pallor
- sweating
- hearing problems (ringing in the ears)
Since the vagus nerve plays on the motility of the digestive system, the patient may also feel nausea before or after fainting, as well as may experience vomiting or diarrhea.
Whilst fainting spells are a major sign of the dysfucntion of the vagus nerve, there can be other longterm symptoms such as IBS (irritable bowel syndrome), weight loss or weight gain, chronic fatigue or anxiety. If you're experiencing these additional complications, you can consult your doctor to find out the best treatment to help relieve those symptoms.
Causes of Vagus Nerve Dysfunction
There are several factors that can contribute to vagus nerve dysfunction. Psychological circumstances, such as intense stress or a strong surge of emotion (for example, the sight of blood) or physical unease (warm atmosphere, prolonged standing, intense effort, intense pain, pregnancy) can stimulate the vagus nerve and act as a trigger.
Some medications can provoke vagus nerve dysfunction, especially those used during treatment for high blood pressure. The vagus nerve works to regulate the heart rate by triggering certain muscles. When the vagus nerve overreacts, it can cause a sudden drop in blood pressure which can lead to vasovagal syncope (a fainting spell).
What to Do in the Case of Vagus Nerve Dysfunction
If you experience vagus nerve dysfunction, it is recommended as a first aid to lie down and raise your legs for a few minutes. This allows the blood to move more easily to the heart and brain, allowing for the restoration of normal blood pressure.
If you are unsure whether or not you are experiencing vagus nerve dysfunction, it is advised to call for help. This is because suddenly losing consciousness can cause trauma in some cases.
In the case of repeated vagus nerve dysfunction, it is important to consult a doctor who can perform a clinical assessment in order to deduce the source as well as treatment.
