Most people know that ear infections– whether they’re in the outer, middle, or inner ear– are caused by viruses or bacteria. Such ear infections often happen during a bad cold or even pneumonia. But unlike infections, allergies aren’t caused by germs. Allergies are caused by normal everyday things such as pollen or dust or cat dander. Can allergies alone cause ear infections?
The short answer: Allergies alone cannot directly cause an ear infection of any type. But allergies can “set the stage” inside the ear and make it easier for an infection to take hold in the first place.
That’s because an allergic reaction sets up inflammation in the delicate lining of the nose, throat, and ear canals. This inflammation can damage the lining enough to let viruses and bacteria get a foothold in the broken, irritated surfaces. The germs start multiplying and very soon an ear infection begins– even if the person was never sick with a cold first.
Some studies show that children who were breastfed tend to get fewer ear infections later on. This may be because breastfeeding strengthens the infant’s immune system, making the child more resistant to nasal allergies and the damage they can cause to the lining of the ears, nose, and throat. This, in turn, makes the child more resistant to ear infections.
Outer ear infection due to allergy
Otitis externa translates as “ear inflammation outside.” It means that the ear canal between the outside opening of the ear and the eardrum inside is inflamed and possibly infected.
Swimmer’s ear, which is the irritation and subsequent infection of the outer ear canal after being in water for long periods, is a common form of otitis externa.
It’s possible for a person who wears a hearing aid for many hours a day to create irritation within the ear canal. And now it seems that everyone is wearing a listening device of some sort for long periods of time: headphones, earbuds, AirPods, AirBuds, or Bluetooth, just to name a few. All of those, especially if not cleaned properly, can irritate and damage both the outer ear itself and the outer ear canal.
Surprisingly, a common cause of allergic reactions is certain antibacterial medicines used in an effort to clear up an infection in the outer ear canal. Do not place any drops or creams inside the ear canal except as ordered by your medical provider, as some antibacterial medicines can cause an allergic reaction within the ear canal. They may also cause ototoxicity, which is damage to the deep inner ear that results in hearing loss.
Sometimes the entire outer ear itself is included in the diagnosis of otitis externa. The outer ear canal may or may not be involved with it. If a person is allergic to certain substances and those come into contact with the outside of the ear, then irritation, inflammation, and skin damage will occur.
As we’ve seen, this damage can allow bacteria to enter the skin and cause an infection. This infection can then spread to the outer canal within the ear.
There are a number of common allergens that can affect the outer ear. Some people are allergic to the different metals used in earrings. And again, the constant use of headphones and other listening devices can produce long-term irritation and breakdown of the skin of the outer ear.
Middle ear infection due to allergy
Otitis media translates as “ear inflammation middle.” It means that the ear canal between the far side of the eardrum and the deeper inner ear is inflamed and possibly infected.
This middle section of the ear is connected to the throat by the eustachian tubes. These tubes can become inflamed due to an upper respiratory infection (a cold) or from the irritation caused by an allergic reaction in the nose and throat.
Either condition can make the tubes become swollen and blocked. If this happens, the tubes cannot drain fluid as they normally do. The fluid becomes a breeding ground for bacteria and an infection can easily take hold, leading to pain and pressure in the middle ear.
This is how allergies, whether they are seasonal or happen all year long, can lead to middle ear infections. The heavy irritation produced by the allergens causes a breakdown in the skin of the ear canals and in the mucus membranes of the nose, throat, and eustachian tubes. This creates a “highway” that lets viruses and bacteria get inside and travel to the middle ear.
There are three types of middle ear infections:
1. Acute otitis media. “Acute” means that the infection comes on quickly and rather suddenly, within hours. But if an allergy caused the irritation and inflammation that allowed the infection to take hold, that allergy will have been going on for weeks or months before the infection is seen.
2. Otitis media with effusion (OME.) “Effusion” simply means “fluid.” OME refers to the way that fluid and mucus remain in the middle ear even after the infection has cleared up. The person continues to feel pressure within the ear, and hearing may be affected.
3. Chronic otitis media with effusion (Chronic OME.) “Chronic” means the condition persists, is resistant to treatment, and never really gets any better or any worse. In Chronic OME, the inflammation, fluid, and pressure remain within the ear canal and may cause long-term damage to the person’s hearing.
Inner ear infection due to allergy
Otitis interna translates as “ear infection inside.” It is also called labyrinthitis, after the structures of the deep inner ear.
Unlike the other two types of ear infections, otitis interna is not caused by allergies because the structures are too deep within the head to be directly affected by allergens. Instead, it is caused by other infections that spread to the inner ear from the sinuses, teeth, or throat.
When treating persistent ear infections, consider treating allergies, too
Whenever a person has persistent, recurring ear infections– whether they affect the outer, middle, or inner ear– the person may be given repeated courses of antibiotic medicines and antimicrobial creams with little to no improvement. The longer the infections go on, the greater the chance of permanent hearing damage.
In such a case, it is possible that allergies are playing a part. It can certainly be helpful to test for allergies and see if they may be an underlying cause of recurring and persistent ear infections.