Anosmia: why the sense of smell disappears and what to do about it

Lately, loss of smell, or anosmia, has been strongly associated with COVID-19. Indeed: this is one of the most common and most characteristicCOVID-19 and anosmia: A review based on up-to-date knowledgesymptoms coronavirus infection. However, the ability to perceive smells disappears not only because of the coronavirus - there are much more probable and often no less dangerous reasons.

Where does anosmia come from?

The first step is to understand how we smell. In general terms, this happensLoss of smell in the following way.

The odor molecules enter the nose and nasopharynx. They are picked up by the olfactory receptors. They transmit a signal that encodes the characteristics of scent molecules to the brain. He analyzes the message, and we realize: it smells like strawberries!

Failure in any of these stages - capturing molecules, transmitting a signal or analyzing it in the brain - leads to the fact that we lose the ability to recognize smells. This is how anosmia arises.

In rare cases, people are born without a sense of smell. This is called congenital anosmia.What Is Anosmia?.

Anosmia can be temporary or permanent. It depends on at which of the stages of odor trapping the failure occurred. Here are the most common reasonsWhat Is Anosmia? loss of smell.

Problems with the nasal mucosa

Most often, the sense of smell is impaired due to inflammation and edema of the mucous membrane and the accompanying abundant secretion of mucus (snot). Under such conditions, molecules of odorous substances simply cannot get to the olfactory receptors.

1. Acute sinusitis. He is also an acute inflammation of the sinuses. Depending on which sinuses are inflamed, there are different types of sinusitis: sinusitis, frontal sinusitis, ethmoiditis.
2. ARVI.
3. Flu.
4. Pollinosis. He's also a hay fever: that's the name of a pollen allergy. Pollinosis leads to the so-called allergic rhinitis - swelling of the mucous membranes and severe rhinitis.
5. Non-allergic rhinitis. In this case, we are talking about chronic rhinitiswhich is not related to allergies.
6. Smoking. If you smoke a lot, tobacco smoke can cause inflammation of the lining of your nasal passages.

Blockage of the nasal passages

The sense of smell can disappear if there is some obstruction in the nose that prevents odorous substances from reaching the receptors.

1. Nasal polyps. This is the name of soft benign formations that develop on the mucous membrane of the nose or sinuses due to chronic inflammation. Small polyps are usually not a problem. Large ones, on the other hand, can block the flow of air through the nose, making it difficult to breathe and creating a feeling of constant congestion.
2. Curvature of the nasal septum.
3. Tumors. Including malignant ones.

Damage to the brain or nerve fibers

It is for this reason that it is assumedCOVID-19 and anosmia: A review based on up-to-date knowledge scientists, the sense of smell disappears with COVID-19. The aggressive coronavirus affects not only the respiratory system, but also the nervous system. As a result, the olfactory receptors simply cannot transmit the message of the detected odor molecules to the brain. However, nerve fibers can be damaged for other reasons.

1. Aging.
2. Dementia This is the name of a pathological process in which brain cells are damaged or destroyed. The most common types dementia - Alzheimer's and Parkinson's diseases. Deterioration of smell is one of the earliest symptoms of incipient brain problems.
3. Multiple sclerosis. This disease is accompanied by damage to the nervous tissue.
4. Diabetes. This disease, among other things, destroys nerve fibers.
5. Hypothyroidism Taste and smell are sometimes impaired due to insufficient production of thyroid hormones.
6. Cerebral aneurysms. Aneurysms are bulges that appear on the walls of arteries. One of these aneurysms can damage nearby nerve fibers or obstruct signal transmission.
7. Burns of the nasal mucosa. For example, caused by inhalation of certain chemicals.
8. Monotonous meager food. A lack of nutrients in the diet can disrupt the brain.
9. Taking some medications. Sometimes the culprit behind the loss of smell isLoss of smell antibiotics, high blood pressure medications, and antihistamines.
10. Stroke.
11. Alcoholism.
12. Traumatic brain injury or brain surgery.
13. Brain tumors.

What to do if the sense of smell has disappeared

The universal advice is to see a therapist. Moreover, as soon as possible: sometimes the loss of smell speaks of really serious diseases, and the earlier the diagnosis is made, the higher the chances of recovery.

The doctor will ask you about your health and other symptoms, and will conduct an examination. Often this is enough to find out the cause of anosmia - a cold, hay fever, burns of mucous membranes are easily diagnosed. If you can't figure out right away why your sense of smell has disappeared, the doctor will suggest you undergo additional examinations:

• Take a blood test to rule out problems with hormones or, let's say, lack of nutrients.
• Get a CT (computed tomography) or MRI (magnetic resonance imaging) scan of the brain to look for possible tumors, blood vessel problems, or damage to nerve tissue.
• Perform nasal endoscopy. During this procedure, the doctor uses a probe to examine the nasal passages and sinuses.

Treatment for anosmia depends on the cause. If the loss of smell is associated with a common cold, hay fever, or ARVI, special therapy is not required: it is enough to recover - and the ability to smell will return. Surgical techniques sometimes help. For example, your doctor may recommend removing polyps or correcting a deviated nasal septum.

In more serious cases, when the loss of smell is caused by the destruction of nerve tissue, prescription hormonal and other medications will be required. They will no longer be prescribed by a therapist, but by a specialized specialist - a neuropathologist or psychiatrist.

Unfortunately, it is not always possible to cure anosmia. And you also need to be ready for this.