Understanding the Science Behind the Asthma Itch

So, I wrote an article called The Asthma Itch: Understanding the Link Between an Itchy Chin and Asthma. Asthma researchers tend to refer to it as "prodromal itching." It's when your chin and neck itch during or just prior to asthma attacks.

After the article was published to our Facebook page, a community member (one of you) asked:

"Yes, my chin, neck, and back will itch just before an attack. I always thought it was due to my asthma issues. Is there a reason why this occurs?"

Yes. The itching may involve more than just the chin. Your head may itch. Like, just under the skin. Your chest may itch. Your lungs may appear to itch. So, itching can feel different. It can take place in areas other than your chin and neck.

What the science says about the asthma itch

There are a couple of theories here.

1. Unknown etiology: The cause remains unknown. It remains a mystery even to the best experts, researchers, scientists, and physicians. They simply do not know what causes prodromal itching. This is the most common theory. This is the humble theory.
2. Histamine itch: This theory postulates that allergies trigger that itchy feeling that precedes asthma attacks. Exposure to allergens increases histamine, the same chemical behind many allergic asthma symptoms. So, elevated histamine levels are thought to cause that itchy chin and neck.¹

These theories may also help explain itchy lung.

That's basically all we have as far as theories. Or, it's all I can find. Perhaps one of you has access to some better theories. If so, please do share in the comments below.

Experiencing prodromal itching in childhood

The "Asthma Itch" really interests me. It's interesting because I experienced it as a kid. The first time I shared this symptom was during an asthma education class at National Jewish Hospital/National Asthma Center in 1985.

The topic of one class was "Early Asthma Warning Symptoms." We were asked to list our own early warning symptoms on a sheet of paper. We were then asked to share our early warning symptoms with the other kid asthmatics in the group. Many of the symptoms were shared by all of us, but a few symptoms were unique to me, including an itchy chin and neck

This was the first time I learned that we all have our own "unique" asthma symptoms. We all have unusual asthma symptoms.

I never thought much else of it until about 30 years later. I came upon a book by Dr. Henry Hyde Salter. His book was titled On Asthma: Its Pathology and Treatment. What a great book about asthma.

Dr. Salter described asthma so explicitly. In fact, he was the first doctor to write such a detailed book on asthma, hence the title. This is probably why it became THE most famous asthma book of the second half of the 19th century. And, as you make it to page 38, you will see that he described our topic for today: "Asthma Itch."

He wrote:

"One curious symptom of asthma, which I have found present in a large number of cases (I am not sure it is not universally present), but which I have never seen noticed in any treatise on the subject, is itching under the chin. I have often known that the breathing of asthmatics was tight, and told them so, from seeing them scratching and rubbing their chins. The itching is incessant, and of an indefinite, creeping character; but although it is impossible to help scratching it, the scratching does not relieve it. It is often accompanied by the same itching sensation over the sternum and between the shoulders, especially between the shoulders. It appears the moment the first tightness of breathing is felt and goes off when the paroxysm has become confirmed…"²

He went on to describe some theories. He said it may be associated with inflammation and bronchospasm. He also noted:

"But I think it is the most strongly marked of all in the asthma that accompanies hay fever."²

Of course, now we define hay fever as allergies. And now we have an asthma subgroup called allergic asthma. This is the most common asthma subgroup. So, if true, this would confirm our modern theory that histamine causes it, since histamine causes your allergy symptoms, including many allergic asthma symptoms.

But some people without allergies also experience the asthma itch. So, could histamine also cause the asthma itch in these asthmatics? Or does this drive us back to theory #1, that the cause is of unknown etiology?

Key takeaways about the asthma itch

It's neat to know you are not alone if you experience the asthma itch. If you're curious why it happens, it may be histamine, especially if the itch shows up alongside other allergic asthma symptoms. It could also be something else entirely. So, what do you think? Do you experience the asthma itch? What do you think causes it? Let us know in the comments below.