Capsaicin Spray to Treat Neuropathic Chronic Cough

Image by Daniel Risacher in Wikipedia

I recently learned of this unusual form of treatment to help with neuropathic chronic cough by respected laryngologist Dr. Robert Bastian. Capsaicin is what provides the heat in chili peppers and has been used alternatively as an irritant to induce cough in the pulmonary literature, but also numbness in chronic pain situations.

As it pertains to laryngeal sensory neuropathy (LSN) or sensory neuropathic cough (SNC), it does not actually fix anything, but rather just helps reduce the symptoms of the chronic cough leading to reduction in frequency and severity. It is hypothesized to help with the neuropathic cough by nerve desensitization by exhausting the internal supply of substance P, a neurotransmitter.

Typically prepared at 0.03% strength by a compounding pharmacy, it is sprayed directly against the back wall of the mouth (not on the tongue or palate). The "heat" will be felt for about 5 minutes. Do not eat/drink for 10 minutes to prevent capsaicin neutralization. Use 4 times per day for 2-3 weeks before deciding whether it is helping.

How to Apply the Capsaicin

These are the instructions patients should follow when applying the capsaicin spray:

1. Stand in front of your bathroom mirror, open your mouth widely, and try to look as far back into your mouth as possible.
2. Depress your tongue so that, if possible, you see the back wall of your throat, and not just your tongue or palate.
3. Take a deep breath, hold it in, and aim the capsaicin spray straight back, attempting to hit the back wall of the throat, and not the front of the mouth. Immediately after spraying, exhale and swallow. You will feel the “heat” of the capsaicin for at least 5 minutes. DO NOT INHALE WHEN YOU SPRAY!!!
4. Do not eat or drink anything for a minimum of 10 minutes before or after using the spray. This is so that ingested substances do not inadvertently “neutralize” the capsaicin (particularly milk, citrus, salt, etc.).

Repeat this routine four times a day for a minimum of two weeks (three is better), before deciding whether or not capsaicin is a worthwhile option.

According to the experience reported by Dr. Bastian, this capsaicin oral spray can help with cough symptoms in one of 3 ways:

1. It may ultimately reduce frequency and severity of cough after initial period cough worsening.
2. It may act as a counter-irritant to abort or minimize a cough attack. Often neuropathic cough is preceded by a "tickle" in the throat. Some patients will use the capsaicin spray as soon as they feel this tickle thereby reducing the duration of subsequent cough (anecdotally, a cough may last only 20 seconds rather than 2 minutes).
3. Capsaicin spray can be used as a cough scheduler. Using this spray will often trigger a coughing attack... but than there will be an unusually long period of being cough-free.

According to Dr. Bastian, capsaicin spray is the fourth thing to try when dealing with neuropathic cough.

At least for me...

Step 1) Typically, after neuropathic cough is finally diagnosed, treatment is initially attempted with neuropathic medications including gabapentin, amitriptyline, pregabalin, etc.

Step 2) Should all these medications fail to help, I than try botox injections to the vocal cords. (More info on botox injections to address chronic cough here.)

Step 3) Should botox fail to help, injection of the superior laryngeal nerve with lidocaine or marcaine is attempted. Potentially, if relief is obtained with this type of injection without significant side effects, this nerve could potentially be surgically cut to make the effects "permanent."

Step 4) Should that method fail to work, capsaicin oral spray can be tried as a last resort.

Keep in mind, that capsaicin oral spray is not used to treat generic chronic cough. It is used to treat NEUROPATHIC chronic cough. In fact, this spray may make the cough worse if the cough is reflux induced (spicy things exacerbate reflux).

More info on laryngeal sensory neuropathy causing chronic cough can be found here.

Reference:
The Use of Capsaicin for Sensory Neuropathic Cough. Bastian Medical Media 7/31/14