Acetylcholine is one of the body’s most important neurotransmitters. What is acetylcholine?  You can’t see it, you can’t measure it, but it is critical for your health.

Acetylcholine – Critical for Optimal Health

By Dr. Diana Driscoll

Acetylcholine is a neurotransmitter — a chemical messenger that allows your nerves to communicate. In the brain (the central nervous system) it allows your neurons to communicate. This allows you to think clearly and to form short-term memories. Without optimal acetylcholine levels for the brain, cognition becomes sluggish, and brain fog can occur.

Your muscles use acetylcholine, too (the peripheral nervous system).  Low acetylcholine levels can result in weakness and fatigue.

Acetylcholine is also required by the autonomic nervous system — the system of the body that you don’t need to think about.  The functions of the autonomic nervous system include heart rate, blood pressure, breathing, blinking, digestion, and many others! The autonomic nervous system controls your vagus nerve which is the anti-inflammatory system of the body. When it is not performing optimally, chronic inflammation can occur. Your vagus nerve (via the messenger acetylcholine) controls every aspect of digestion including: movement of food through the upper GI tract beginning with swallowing, normal stomach acid production, the opening of the pyloric valve at the base of the stomach allowing food to pass into the intestines, movement of stool through the intestines, gallbladder functioning to release bile for digestion of fats, pancreatic functioning to release digestive enzymes, and movement of the stool (“peristalsis”) to trigger a bowel movement.

The parasympathetic nervous system — the “rest and digest” system of the body — depends upon acetylcholine. Acetylcholine is the chemical messenger that allows your body to calm down after a surge of adrenaline occurs — only then can you get in a relaxed state and begin digestion.

What Causes Low Acetylcholine Levels?

Acetylcholine deficiency can be secondary to genetic errors, chronic illness, chronic inflammation, some medications, and aging. It can be easy to miss because there is no blood test for it. Low acetylcholine levels also occur in certain types of poisoning (anticholinergic poisoning). When patients ingest massive doses of anticholinergics (such as an accidental poisoning with atropine), anticholinergic poisoning occurs. The symptoms of anticholinergic poisoning must be recognized based on presentation (signs and symptoms). When low acetylcholine levels occur at lower levels than those in anticholinergic poisoning, the presentation is easy to miss because it can mimic many other conditions.

Symptoms of Low Acetylcholine found in Anticholinergic Poisoning

Doctors have a mnemonic to remember the presentation of low acetylcholine levels in anticholinergic poisoning: “Blind as a bat, dry as a bone, red as a beet, mad as a hatter, can’t see, can’t pee, can’t poop”. What do these symptoms mean and what other symptoms occur in anticholinergic poisoning?

1. “Brain Fog”, Poor Short-Term Memory:

Acetylcholine is the neurotransmitter needed by the neurons of the brain to communicate with each other. Low acetylcholine causes difficulties with cognition, “brain fog”, and mental fatigue.

2. Fatigue, Especially Fatigue That Worsens With Exertion:

Acetylcholine is required by the peripheral nervous system to allow muscles to work. Low acetylcholine levels result in muscle weakness that worsens with exercise or exertion. The muscles may work for a while, then exhaust their supply of acetylcholine, leading to extreme fatigue.


3. Constipation/Gastroparesis (“can’t poop”):

The vagus nerve requires acetylcholine to assist every aspect of digestion including peristalsis (movement of food/stool through the digestive tract), stomach acid production, opening of the pyloric sphincter at the bottom of the stomach, gallbladder function, some pancreatic function, and opening of the Sphincter of Oddi (which allows bile and pancreatic enzymes to pass into the intestines). Low acetylcholine levels result in chronic constipation and/or gastroparesis. Low acetylcholine levels also cause poor digestion and poor absorption of critical nutrients.

4. Dry Eyes (“dry as a bone”):

Normal tear production is a process of our autonomic nervous system. Acetylcholine is required by the lacrimal gland to produce tears. Acetylcholine is also used by the nerves to tell our bodies when to produce tears. When levels of acetylcholine are low, dry, painful eyes can result. Dry eyes from low acetylcholine are resistant to conventional dry eye treatment unless acetylcholine levels are restored.

5. Orthostatic Hypotension:

Low acetylcholine levels result in low blood pressure when standing, which causes dizziness and weakness.

6. Flushing (“red as a beet”):

Low acetylcholine levels can cause episodes of flushing (redness) on the face. The neck and other parts of the body may also appear flushed. It is common for flushing to be misdiagnosed as rosacea or mast cell activation.

7. Emotional Instability (“mad as a hatter”):

People with low acetylcholine levels will often suffer from the inability to cope with their emotions. Their emotional state can be unpredictable.

8. Chronic Inflammation:

Acetylcholine is needed by the vagus nerve (the anti-inflammatory pathway of the body). Low levels of acetylcholine contribute to consistently high levels of inflammation which can cause pain, atherosclerosis, fatigue, hypercoagulation (easy blood clotting) and premature aging.

9. Fast Heart Rate (Tachycardia):

The parasympathetic nervous system is the body’s “rest and digest” system. When levels of acetylcholine are insufficient, the vagus nerve no longer properly slows down the heart and the body cannot rest properly. The vagus nerve relies upon acetylcholine to stimulate the sinoatrial node of the heart to normalize heart rate.

10. Large Pupils (“blind as a bat”):

Pupil size is a function of the balance between the sympathetic nervous system (large pupils) and parasympathetic nervous system (small pupils). Low acetylcholine levels upset this balance. When the balance is upset, the sympathetic nervous system overrides the parasympathetic nervous system, resulting in large pupils. Large pupils often cause light sensitivity and difficulty focusing.

If you have some of these symptoms and yet you have not been poisoned, you could be dealing with less than optimal levels of acetylcholine, perhaps due to genetics, aging, or inflammation.

How Can You Support Your Acetylcholine Levels?

Parasym Plus™ is the only product patented to gently nudge the vagus nerve PLUS it crosses the blood-brain barrier to support cognition. By supporting acetylcholine levels, Parasym Plus™ also helps maintain normal tear production.

What can we do if we suffer from low acetylcholine levels? Can we provide what our bodies need in a way that also stimulates the vagus nerve? 

Yes, we can.

Diana Driscoll, OD

Diana Driscoll, OD

Founder, Clinical Director at POTS Care

Dr. Diana Driscoll, an Optometrist, is the President of Genetic Disease Investigators, LLC – a research corporation devoted helping people affected by “invisible illnesses”. Now focused on… Read more…


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