The 15 types of allergies (and their characteristics)

Statistics show that 4 out of 10 people in the world suffer from allergies. And this figure, which is already 40% worldwide, continues to grow, so it is estimated that, over the next decade, half of the population will suffer from this disorder, the incidence of which is increasing due to factors such as bad eating habits or pollution.

Hence, with forgiveness of the virus that has changed our lives, allergies are considered, along with obesity, as the great pandemic of the 21st century. We are talking about immunological disorders that cause the person who suffers, when exposed to a substance that is not harmful to the body known as an allergen, to trigger an excessive immune reaction that, although it is often mild and not serious, sometimes it can be lethal.

As we well know, we can develop allergies to practically any substance in the external environment, being allergies to pollen, mites, certain foods (allergies to nuts, shellfish, fish, fruits, eggs stand out). , milk, soy, etc), animal dander, insect bites, mold, latex, certain medications, cosmetics or nickel, the most common.

But from a clinical point of view, it is very interesting to know not only which are the most frequent allergies, but also how these immunological disorders are classified. And this is precisely what we are going to do in today's article, and as always with the help of the most prestigious scientific publications. Let us begin.

What are allergies?

An allergy is an immune disorder in which, due to a genetic defect, the person has a hypersensitivity to a harmless substance known as an allergen.. In this sense, allergies are pathologies of immune origin in which exposure to this allergen triggers an excessive immune reaction that is indeed harmful to the body.

When the allergic person is exposed to this agent, a substance that in other people does not trigger any type of reaction, their immune system believes that said substance is harmful to the body, so it turns on the neutralization mechanisms as if it were an infection. will try Thus, allergies are based on a hypersensitivity to a non-dangerous substance that the immune system, due to poor genetic "programming", believes is a threat.

The immune reaction is based on inflammation in the region of the body where the immune system, by contact with the allergen, is acting, being generally the digestive system, the respiratory tract or the skin. But there are times when the immune imbalance is so severe that the hypersensitivity response turns into severe symptoms, and can even lead to life-threatening anaphylactic shock.

Be that as it may, allergies appear because the immune system becomes unbalanced (due to a combination of not only genetic, but also environmental factors) and develops immunity, that is, it produces antibodies against a particle that is harmless to our health. Thus, every time we are exposed to it, the antibodies will move towards it and signal the immune cells to trigger the inflammation response.

This origin so deep in the immune system means that, as a general rule, an allergy has no cure. But there are treatments that help control symptoms during an allergic reaction., consisting of the administration of drugs that reduce the synthesis and release of histamine, the molecule that is responsible for inflammation and, therefore, for the clinical signs of the allergic attack. In case there is a risk that the person will go into anaphylactic shock, the most used option is the injection of adrenaline (also known as epinephrine), which, as an emergency in the event of possible anaphylaxis, dilates the airways and increases the heart rate to avoid it.

At the same time, for the most severe cases of allergies, there is the alternative of immunotherapy, a treatment based on regularly and periodically injecting the patient with purified allergens so that the body "gets used" to them and the reaction becomes less and less strong. Thus, before a real exposure, the attacks will be milder.

How are allergies classified?

After having extensively analyzed the causes, symptoms and treatment of allergies, the time has come to focus on answering the question that has brought us together here today: What types of allergies are there? Well, these can be classified according to different parameters that we have collected so that you can discover the main classes of allergies. Let's see them.

1. Dermatological allergies

Dermatological allergies are those in which the inflammatory symptoms due to exposure to the allergen is located on the surface of the skin, causing rashes, sores, skin eruptions, hives or eczema. It is, along with the following, the most common type according to the symptoms.

2. Respiratory allergies

Respiratory allergies are those in which the inflammatory symptoms due to exposure to the allergen are located in the lower respiratory tract, mainly at the level of the bronchi, making it difficult to breathe and causing coughing, wheezing or asthma problems.

3. Eye allergies

Ocular allergies are those in which the inflammatory symptomatology due to exposure to the allergen located in the eyescausing a symptomatology typical of conjunctivitis, that is, with eye irritation, redness of the eyes and tearing.

4. Digestive allergies

Digestive allergies are those in which the inflammatory symptomatology due to exposure to the allergen is located in the gastrointestinal tract, being obviously linked to food allergies and causing problems of stomach pain, vomiting and diarrhoea.

5. Nasal allergies

Nasal allergies are those in which the inflammatory symptomatology due to exposure to the allergen located in the upper respiratory tract. This gives rise to clinical signs such as nasal itching, mucus production and sneezing, thus having a symptomatology very similar to that of a cold but with sudden onset.

6. Food allergies

Now we have seen what allergies exist according to the symptoms. Now is the time to see them depending on the nature of the allergen. And in this context, we first come across food allergies, those in which the person develops hypersensitivity to the proteins in certain foods. They affect 3% of the population and the most frequent are nuts, shellfish, fruits, fish, milk, soybeans, wheat, eggs and peanuts.

7. Drug allergies

Drug allergies are those in which the person develops hypersensitivity to some component of a drug. Allergy to penicillin and aspirin are some of the most common, but they can develop towards any component, both active ingredient and complementary substance, of a medicine. Being the potentially most serious, it is important to know if we suffer from any.

8. Biological allergies

Biological allergies are those in which the person develops hypersensitivity to some substance from a living being, that is, they occur by contact with a biological structure. Allergies to pollen, animal dander, mites, mold or insect bites are the most common.

9. Chemical allergies

Chemical allergies are those in which the person develops hypersensitivity to any substance of non-biological origin but not associated with a medication. That is, all those allergens of a chemical nature fall into this group. Allergies to certain cosmetics, nickel or latex are the most common.

10. Seasonal allergies

Now that we have seen what types of allergies exist according to the origin of the allergen, it is time to analyze the parameter that classifies them according to the time, mode or place of exposure to it. In this context, we will first talk about seasonal allergies, which are those so common in which the allergic person tends to have hypersensitivity reactions in a few specific periods of the year, being spring, due to the pollen problem, the most common.

11. Occupational allergies

Occupational allergies are those in which the person suffers hypersensitivity reactions due to exposure to allergens present in their workplace, being a common form of allergy in the chemical industry or in research environments or handling of biological agents. Thus, it is an allergy that is triggered in the work environment.

12. Inhalation allergies

Inhalation allergies are those in which exposure to the allergen occurs through an introduction of the same by aireither through the nostrils or through the mouth. It gives rise to nasal or respiratory allergies generally associated with pollen.

13. Ingestion allergies

Ingestion allergies are those in which exposure to the allergen occurs through its introduction through the digestive tract, that is, with ingestion through the mouth and consequent entry into the gastrointestinal tract. The most common are, of course, food and drug allergies.

14. Contact allergies

Contact allergies are those in which exposure to the allergen occurs through direct contact on the surface of the skin. Therefore, being generally linked to biological allergies, it causes dermatological reactions.

15. Inoculation allergy

And we end with the surely it is the most dangerous of all and, luckily, the least common. Inoculation allergies are those in which exposure to the allergen occurs through the intravenous route, that is, by direct injection into the bloodstream. This means that the reaction, which is obviously of medicinal origin, can occur systemically, since it is being inoculated directly into the circulatory system.