Irritable Larynx Syndrome (ILS)
Irritable Larynx Syndrome (ILS) is a cluster of symptoms not associated with a specific disease process. Individuals with ILS can have any combination of the following complaints:
- Chronic cough or throat clearing; sensation of need to clear throat
- Globus sensation (feeling of lump or some other sensation in the throat)
- Throat irritation or burning sensation
- Tightness of throat or neck
- Effort or pain with swallowing
- Paradoxical vocal fold motion (sensation of difficulty inhaling)
- Laryngospasm (tightening of throat causing choking or difficulty inhaling)
What Causes ILS?
ILS works in the same way as a mosquito bite: scratching it feels better for a few moments, but in the long run scratching actually makes the itch worse. In the same way, when individuals experience mild irritation in their throats for some reason, they might not realize that they’ve begun “scratching” the “itch,” (throat clearing) but over time the irritation worsens and becomes more noticeable. This is how earlier, milder symptoms can be the precursors to more-severe symptoms. Chronic irritation of the mucosa in the laryngeal area can cause changes to the nerve pathways; they can become hyper-excitable, so that it only takes a small irritation to have a large sensory response (like a cough). It’s nice that the nervous system can learn, but in this case it has backfired.
Here are some possible irritants that can start the chain reaction (most individuals have more than one):
- Upper respiratory infection with cough
- Post Nasal Drainage
- Allergens (e.g. tree, mold, pollen, pet dander)
- Cigarette smoke or other kinds of smoke
- Odors (e.g. perfume, hairspray)
- Food sensitivities
- Harsh chemicals/cleaners
- Cold Air or Hot/humid air
- Strong Emotions (e.g. anxiety, stress)
- Hyperfunction of the muscles of the vocal mechanism
The Problem of Phlegm in the Throat
Many patients state that they feel “phlegm” in their throat and need to clear it away with coughing or throat-clearing. “Phlegm” is a word to describe the naturally occurring secretions in the throat that are produced by the salivary, and other, glands. Those secretions are very important for the health of the mucosa. In a healthy larynx, the secretions are thin, and are swallowed without being noticed. (We swallow a quart of secretions every day!) In an irritated larynx, the secretions can become dry and thick, leading to the desire to cough or throat clear.
Cough and Throat Clearing
The biological purpose of the larynx is to protect the airway (trachea and lungs). Coughing and throat clearing are mechanisms that are meant to assist in the protection of our airway. When we feel something such as liquid, food, saliva, dust, etc. near our vocal folds, we will clear our throats and cough as a protective reflex. We also cough or throat clear if our airway is irritated.
Why can chronic coughing and throat clearing be harmful?
A cough is produced by squeezing the vocal folds together, building up pressure in the lungs, and then quickly forcing the vocal folds open to clear away whatever might be getting too close to our airway. This can be traumatic to the vocal folds, irritating them in the same way that our hands would be irritated if they were being clapped together over and over. Coughing for a long period of time can cause the mucosa of the larynx and vocal folds to become hypersensitive, making it feel like something is threatening the airway. The vocal folds feel the need to cough or throat clear even when there isn’t an actual physical threat to the airway. The chronic coughing or throat clearing results in even more coughing or throat clearing.
- ILS is associated with worsening irritation and sensitivity of the laryngeal area. This irritation and sensitivity are often the precursors to more-severe symptoms such as chronic cough and/or coughing fits, and significant difficulty breathing.
- Although not all patients experience all of the symptoms listed above, we find that the symptoms tend to become worse in severity and one symptom can lead to others.
Evaluation of ILS
At the Lions Voice Clinic, an otolaryngologist and a speech-language pathologist work as a team to determine if ILS is a problem. Medical evaluation and laryngeal examination rule out any other cause for the symptoms. Some medical treatment may be advised. Functional evaluation determines whether there are behavioral or lifestyle factors that are contributing to the symptoms.
Treatment of ILS
Treatment of ILS addresses the cause of irritation. This can include:
- Treatment of Acid Reflux. This may include: Medications (what your MD prescribes), Dietary Precautions (what you eat and what supplements you take), Lifestyle Precautions (when you eat, avoiding environmental irritants), and Mechanical Precautions (how much pressure you put on your lower esophageal sphincter).
- Functional Speech Therapy with a Speech-Language Pathologist (SLP). Your SLP will educate you about the disorder, help you improve the environment of your laryngeal mucosa to reduce irritation, improve the movement and function of your larynx, and help reduce muscle tension and restore muscle balance. An important part of treatment is teaching you techniques and strategies to avoid or suppress the cough or throat-clearing.
- Further Medical treatment is sometimes used to restore the medical basis for normal function and sensation. Your MD will discuss these possibilities with you if they are relevant.
Definitions: Terms used on this page.
Vocal Fold: the more correct term for Vocal Cord.
Mucosa: the tissue on the surface of the vocal fold, also referred to as mucosal tissue.
For other anatomical terms, please see the About the Voice page for explanations.