Do You Need to Stimulate Your Vagus Nerve? What You May Be Missing!

By Dr. Diana Driscoll, Optometrist

The vagus nerve is the major nerve controlling the parasympathetic nervous system - the system of the body that allows us to rest and digest.

The vagus nerve controls virtually every aspect of digestion - from stomach acid production to motility. When this nerve fails, digestion suffers, and malabsorption can occur.

After you experience "fight or flight" (the sympathetic nervous system is activated), the vagus nerve also allows you to calm down and normalize your heart rate and breathing. It is the "rest and digest" system of the body.

The vagus nerve is also the anti-inflammatory nerve of the body! Once the need for inflammation passes, the vagus nerve sends out signals to the inflammatory cells to stop releasing damaging inflammatory cytokines and other chemicals. When the vagus nerve is not working well, inflammation can become chronic (and cause further damage).

So, Do You Need to Stimulate Your Vagus Nerve?

With the new science released on the importance of the vagus nerve, I’ve seen many people go to great lengths to stimulate their vagus nerve. They may splash water on their face, sing or hum, or meditate, for example. Many patients are buying vagus nerve stimulators to get their vagus nerve working. But is this necessary, effective, or even desirable?

If you have been stimulating your vagus nerve, but not getting the results you hoped for, something may be missing!

It is critical to understand that the vagus nerve is part of the autonomic nervous system - the system of the body that works without our effort (it is automatic). As the "automatic" nervous system, no one should need to make it work. You shouldn’t need to “make” your stomach produce stomach acid, nor do you need to “tell” your gallbladder to release bile for digestion, for example. This happens all by itself as a part of the autonomic nervous system. And thank goodness! Can you imagine going through life needing to tell your body when to produce tears, change your blood pressure, eject pancreatic enzymes, or have a bowel movement? The body is magnificently made so that the autonomic nervous system doesn’t need our input! We shouldn’t need to make the vagus nerve work!

We shouldn’t need to stimulate our vagus nerve.

So if the nerve doesn’t appear to be working well, or if stimulation is not getting the desired response, what can we do? Let’s look closely at the science.

What else could cause a vagus nerve problem and how can we return to normal autonomic functioning without actively stimulating the nerve?

First, we need to understand that nerves work by receiving a signal, then the signal travels down to the end of the nerve where a chemical is released (the neurotransmitter) which then jumps over a small gap (a “synapse”) to land on a receptor, causing an action.

When this process is broken, we need to consider the possibility that the nerve is damaged. The vagus nerve (“the wandering nerve”) is the longest cranial nerve in the body and is prone to damage. Abdominal surgery, heart ablation, gastric sleeve, and whiplash, for example, can all damage this delicate nerve. If your nerve is damaged, stimulating it will do nothing. The signal will not pass through the damaged portion in order to release the neurotransmitter.

Secondly, we need to consider that the vagus nerve problem could be a secondary issue. If the problem is actually a neurotransmitter problem, correcting this problem can return normal nerve function. What can affect the neurotransmitter used by the vagus nerve?

This neurotransmitter is acetylcholine. There are some genetic conditions that influence its production. A genetic problem with the manufacturing of acetylcholine means that you cannot produce enough for maximal vagus nerve function. Again, stimulating the nerve will not correct the problem -- it is a neurotransmitter problem, not a nerve problem.

Also critical for acetylcholine production are specific nutrients. If you suffer with nutrient malabsorption for any reason, the production of acetylcholine can be restricted.

Some inflammatory cytokines and chemokines block the release of acetylcholine. If this is occurring, stimulating the nerve will not be effective.

How can you recognize a problem with acetylcholine as the issue resulting in vagus nerve problems?

When problems with acetylcholine occur, the symptoms extend beyond the vagus nerve. If these symptoms are present, the true problem may be an acetylcholine problem -- not a vagus nerve problem. What symptoms or signs should you consider?

When acetylcholine is not being produced or released properly, symptoms of anticholinergic syndrome occur. Anticholinergic syndrome occurs when a patient has ingested a drug that breaks down acetylcholine (such as atropine -- eye drops that dilate the pupil). These symptoms include brain fog, easy irritation, moodiness, visual snow, fatigue, constipation, poor cognition and a decrease in short-term memory, dry eyes and dry mouth. These symptoms reach far beyond vagus nerve problems.

Watch Dr. Diana Driscoll discuss the results of her research in anticholinergic syndrome in Chronic Fatigue Syndrome at AAEM 2019

If the true problem involves the neurotransmitter, the problem with the neurotransmitter must be corrected (as opposed to the vagus nerve). Correcting the acetylcholine problem can then resolve the symptoms of vagus nerve problems AND the additional symptoms of low acetylcholine.


  • If the vagus nerve is damaged, stimulating the nerve will not work.
  • If there is a genetic issue with the production of acetylcholine, stimulating the nerve will not work.
  • Some nutrients are essential in the production of acetylcholine. Deficiencies of these nutrients result in insufficient acetylcholine and stimulating the vagus nerve will not work.
  • If the problem is one of acetylcholine, stimulating the vagus nerve will do nothing to help with other systems of the body that depend upon acetylcholine (tear production by the lacrimal nerve and cognition by the central nervous system, for example).

It took years for me to work through this problem! I collected symptom spreadsheets over 4 ½ years for patients with numerous “invisible illnesses” such as ME/CFS (Chronic Fatigue Syndrome), Fibromyalgia, POTS (Postural Orthostatic Tachycardia Syndrome), PTSD (Post Traumatic Stress Disorder), and TBI (Traumatic Brain Injury). The majority of patients displayed the majority of symptoms of anticholinergic syndrome -- a new finding never before reported.

It took even longer to test my hypothesis (beginning with my own body), then begin to approach treatment in a unique fashion. I asked myself if it was possible to come up with an oral supplement that could come into the body quickly to stimulate the (postganglionic) vagus nerve or the receptor itself and yet work around any of the problems with the nerve or with the neurotransmitter affecting the patient. My goals were numerous and included the following:

  • The supplement had to work around any genetic issues with acetylcholine production.
  • It had to cross the blood-brain barrier to supply acetylcholine for cognition.
  • It had to supply necessary nutrients to cover for any deficiency that can lead to low acetylcholine.
  • It had to work even if the (preganglionic) vagus nerve was damaged. Instead, it had to work on the postganglionic vagus nerve (or the receptor itself).
  • To judge effectiveness, I needed to see a bowel movement.
  • It had to support acetylcholine for the lacrimal nerve, normalizing tear production (dry eyes).

No one had ever tried to do this orally before. As such, the result of my work has received four patents to date.

Staying firmly in science gives us the answers. Although my intuition told me that I shouldn’t need to stimulate the vagus nerve with a stimulator (it should work all by itself), the true problems can be easy to miss.

Supporting your vagus nerve with Parasym PlusTM will cover you for any reason you have a problem with the neurotransmitter. You don’t need to know if you have genetic problems with acetylcholine or if your (preganglionic) vagus nerve is damaged. Stimulating your vagus nerve is not necessary.

Supporting your vagus nerve with Parasym PlusTM will cover you for any reason you have a problem with the neurotransmitter. It was critical for my return to health and for that of my children.

Dr. Diana Driscoll, Optometrist

Learn more about Vagus Nerve Support with Parasym PlusTM