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"Medically Unexplained Symptoms"? Always a Wrong Diagnosis

Often ignored are the many ways the body responds to feelings of threat

Key points

  • Every medical symptom is explainable by abnormal structure, genetics, or physiology. "Medically Unexplained Symptoms" does not exist.
  • Most unexplained symptoms arise from the physiological response to a threat, whether actual or perceived; internal or external.
  • The diagnosis of MUS does double damage: It destroys hope and optimism, which have been documented to be anti-inflammatory.
  • Patients suffering from chronic pain already endure such labels as inadequate, complainer, and drug-seeker; MUS adds a deadly component.

“Medically Unexplained Symptoms” (MUS) has become a diagnosis not uncommonly given to patients for whom a cause of suffering has not been found. Many are people experiencing chronic pain and told that they “just have to live with it.” That is simply incorrect. In fact, the body is prolific at generating symptoms; it is part of a basic survival mechanism in the response to threats, whether internal or external.

As Dr. Stephen Porges has eloquently explained, the autonomic nervous system, through the vagus nerve, modulates various physiological states. (1) Its actions are responsible for many kinds of symptoms. The first part of this two-part series explained that MUS is always incorrect and that all symptoms are explainable by a structural abnormality, congenital/ genetic problem, or changes in the body’s physiology. No one should settle for a diagnosis of MUS.

The consequences

Although it is important not to miss a structural problem, it is an uncommon source of symptoms compared to the ones created by your body’s physiology when it is in a prolonged state of heightened threat. The biochemical changes that mark this state give rise to symptoms and illnesses ranging from irritable bowel syndrome to tinnitus to rheumatoid arthritis to depression. Not to mention insomnia, anxiety, OCD, and coronary artery disease. The list is long.

Solving MUS

You experience threat when your stresses overwhelm your capacity to process them. The resultant neurochemical reaction creates many different unpleasant symptoms When you sense real or perceived danger, your body immediately responds with a fight or flight response. Adrenaline, cortisol, and other stress hormones are intended to increase your chances of survival. This response also involves the immune system, which stimulates your inflammatory process to kick into gear. It has been shown the mental threats stimulate the same reaction as do invading bacteria and viruses. The chronic production of inflammatory cells will destroy your own tissues as well as foreign invaders.

There are specific tools and treatments that address each aspect of processing your circumstances: the reactivity of the nervous system—the input—and the final output of the physiological response. They can be used to restore equilibrium and health to the entire system.

The state of the nervous system is directly affected by sleep, exercise, and general nutrition. A history of childhood trauma programs your brain to be continually on the lookout for danger. A mental health professional can help you train your nervous system to be less reactive.

You can modify input to the nervous system in several ways. Cognitive behavioral therapy and ACT (acceptance and commitment therapy) are much-validated techniques for processing traumatic experiences. Expressive writing is another that has been shown to be highly effective for restoring calm to the nervous system in response to all kinds of insult and injury. Cultivating forgiveness is yet another technique for calming mental state in response to injury.

The output, or physiologic state, directly responds to stimulation of the vagus nerve, which is anti-inflammatory. Humming, certain pitches of music, deep breathing, vagal stimulation, and mindfulness/meditation are all calming techniques that work through this tenth cranial nerve.

Why is MUS such a deadly diagnosis?

The worst aspect of the diagnosis of MUS is that it creates despair; it takes away hope. Research has shown that hope, optimism, and a sense of purpose are anti-inflammatory and allow your cells to regenerate and your body to recuperate. (2) So, the MUS diagnosis itself is inflammatory and compounds the sense of threat. Do not accept it at any level.

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Another major reason MUS is so damaging is that many physicians assume it is untreatable, believe nothing more can be done, and refer patients to a psychologist, offering explanations that are all too familiar: “It is in your head.” You don’t have much of a pain tolerance.” “You are just looking for drugs.” You have “secondary gain issues and don’t really want to work.”

The labels keep piling up and, aside from being wrong, none of them are helpful to healing. MUS has a certain finality to it, and it is crushing. It is tragic, because most physicians have not been taught that there is a link between mental/physical threats and the physiological changes that cause physical symptoms. The ultimate tragedy is that with the correct understanding, the symptoms could be treated with minimal cost and risk.

How can you figure this out?

First, it is always important to undergo a medical workup to make sure there is not a structural issue such as vascular disease, pinched nerve, tumor, or an infection.

Second, regardless of the findings of the workup, maintaining your body’s metabolic, immune, and nervous system balance is important. If you require a procedure, your odds of a good outcome will be maximized.

Third, there are many ways to accomplish being in homeostasis, or a state of safety. There are treatments and tools that address your body’s response to your present circumstances.

“Bring it on.”

What does not work for processing stresses is ignoring and suppressing them, which is what most of us have been taught to do. “Just deal with it.” “It is just the way it is.” “There is nothing I can do anyway.” “Bring it on. I can handle it.” Suppressing stress can work in the short-term and even for years. But your body will remain in a defensive state of increased metabolism and inflammation, and it will gradually break down your own tissues. Sustained exposure to stress without the tools to lower your body’s response to it will make you ill and cause serious illnesses.

Three parts of healing

The first step is understanding the nature of chronic disease and the principles behind the solutions. You must also be clear about how your specific life situation may be affecting your symptoms.

Second, every influence on chronic pain that is relevant to you must be addressed —sleep, processing stress, stabilizing medications, and diet/exercise. Social connection and positive life outlook are also anti-inflammatory and reinforce the body’s defenses against chronic disease.

Patients often say, “I have already tried all of these treatments and I am still in pain.” Every treatment does have some beneficial effect, but none are powerful enough to solve chronic pain in isolation.

Finally, no other person, including a health care professional, can see or understand the world through your eyes. That is why taking charge of your care from an increasingly educated perspective is the only possible solution to a person’s mental/physical pain.

In sum, most symptoms reflect your body’s neurochemical response to threats —especially when the stresses are sustained. There is no such diagnosis as MUS, and the term needs to be discarded. The correct term is, “Medically Explained Symptoms” (MES). Do not let anyone tell you otherwise.

MUS must go!


1. Porges Stephen. The Pocket Guide to the Polyvagal Theory: The Transformative Power of Feeling Safe. Norton and Co, New York, NY, 2017.

2. Dantzer R, et al. Resilience and Immunity. Brain Behav Immun (2018);74:28-42. Doi.10.1016.j.bbi2018.08.010

3. Wise BL, et al. Psychological factors and their relation to osteoarthritis pain. Osteoarthritis and Cartilage (2010);18:883-887.