Sensory Neuropathic Cough (SNC)

When coughing doesn’t stop.

Sensory Neuropathic Cough (SNC) is a chronic cough disorder that is thought to have a neurogenic cause.

Sensory neuropathic cough (SNC) ¹ is also sometimes referred to as a cough caused by “laryngeal sensory neuropathy,” or is sometimes grouped within the more general category of “refractory chronic cough.”

Symptoms of Sensory Neuropathic Cough

A person with SNC may cough dozens to hundreds of times per day, often also waking up at night to cough. A few of these daily coughing attacks may become violent and last 30 seconds to several minutes. The person’s eyes may tear up and the nose may run; the person may gag or throw up; the person may leak urine, or worse; a few of our patients have even broken one or more ribs during a violent coughing attack. A key characteristic of SNC is that a coughing attack is typically, though not always, preceded by an abrupt sensation in the throat; this sensation may be described as a “tickle,” a “sudden dry patch,” “like inhaling a powdered doughnut,” “dripping mucus,” or something else.

Possible Explanation for SNC

SNC is thought to be a relative to neuralgia, like post-herpetic neuralgia (persistent pain long after an outbreak of shingles has resolved), or even diabetic neuropathy (“I feel bees stinging my feet”), except that the sensations felt by SNC patients are not painful. With SNC, it may be that the nerve endings in a person’s throat have become damaged, so that they “misfire” and cause this cough-provoking tickling or similar sensations.

Treatment for SNC

Many individuals with SNC have found relief through use of a neuralgia medication, such as amitriptyline ², desipramine ³, gabapentin ⁴, pregabalin, oxcarbazepine, and others. These kinds of medications may help to reduce or abolish a person’s coughing by diminishing the nerve-ending “misfires” caused by SNC. In our experience, patients sometimes need to work through more than one of these neuralgia medication options, at varying dosage levels, before they arrive at a satisfactory degree of relief. Another treatment option that can be tried is capsaicin. For more about treatment, see our second video (SNC: Medications) below.

Table of Contents

Definition of SNC

· Symptoms of SNC

· Possible Explanation for SNC

· Treatment for SNC

Audio Examples of SNC

· Hemoptysis

Still Have Questions?

References

Alternative Languages

Audio Examples of SNC

Interview with a SNC patient

Second interview with a different SNC patient

SNC and throat clearing of 36 Years’ duration

Fourth interview with a different SNC patient

SNC cough phenomenology: different than that of pneumonia, asthma, or acid reflux!

Note: Some aspects of these patients’ experiences are atypical; not all patients have the same experience with SNC.

Photos of SNC

A collection of photo essays demonstrating SNC in various patients.

Bruising from Sensory Neuropathic Cough

Bruise caused by violent coughing (1 of 2)

Closer view of bruise, with small collection of white mucus in the middle.

Bruise caused by violent coughing — Closer view of bruise (2 of 2)

A person with violent sensory neuropathic coughing may injure the vocal cords, as illustrated by this bruise, right vocal cord (left of photo).

Example 2

Bruise from coughing (1 of 3)

This man had an episode of aggressive coughing a week earlier. Note the bruising over the vocal processes, which receive the major collisional force during coughing.

Pre-phonatory instant (2 of 3)

The vocal processes are approaching the point of touching (contact would occur gently with onset of talking and more aggressively with coughing).

Phonation (3 of 3)

Vocal cords are now in full contact. Note the unrelated moderately-severe vocal cord bowing.

Example 3

Bruising from SNC (1 of 1)

This individual occasionally coughs to the point of hoarseness. Particularly noteworthy is the subglottic bruise (arrow, dotted line) caused by profound Valsalva-retching kind of coughing. The rest of the right cord (left of photo) is also bruised.

Hemoptysis

SNC patient (1 of 6)

A very worried patient with sensory neuropathic cough has scheduled a return appointment. On arrival she states that she cannot rest due to a trace of hemoptysis a week earlier. What begins as a simple upper aerodigestive tract examination represented by this view of her normal nasopharynx is easily expanded…

Panoramic view (2 of 6)

Detailed inspection of base of tongue, hypopharynx, and laryngeal vestibule, represented by this panoramic view, also show no abnormality. And the examination can continue…

Lidocaine (3 of 6)

Simple instillation of lidocaine into the trachea allows this view into the upper trachea.

Carina (4 of 6)

And this view, with the carina in clear view.

Right mainstem bronchus (5 of 6)

Deep inside right mainstem bronchus and…

Left mainstem bronchus (6 of 6)

...into left mainstem bronchus also reveal no lesions and no “trail of blood.” Simple watchful waiting for more hemoptysis is acceptable to the patient. CXR is optional in the near-term.

Videos about SNC

SNC, Part I: Coughing That Won’t Go Away

Sensory neuropathic cough is a chronic cough condition that does not respond to the usual treatments. Many individuals who have been coughing for years find relief from treatment with “neuralgia” medications.

SNC Part II: Medications

Dr. Bastian continues from SNC, Part I and introduces potential medications to treat sensory neuropathic cough.

Still Coughing After COVID?

In this video, Dr. Robert W. Bastian explains three explanations for coughing in the context of Covid-19 infection, with emphasis on the potential for sensory neuropathic cough (Phase 3).