Pollen Allergy: Everything You Need to Know

A pollen allergy can manifest itself through respiratory and eye symptoms that are very uncomfortable. Fortunately, there are medications capable of alleviating the condition, as well as measures to reduce exposure.
Pollen Allergy: Everything You Need to Know

Last update: 02 June, 2021

Spring can be one of the most beautiful times of the year due to the large number of flowers and the greenery of the plants. Unfortunately, a pollen allergy can give millions of people a terrible time during those months. Would you like to learn more about this condition? Continue reading!

Pollen is nothing more than tiny granules that contain sperm cells, which are essential for plant reproduction. The production of these granules increases to a great extent during the spring, and can be found in the atmosphere in high concentrations.

Pollen allergy or pollinosis is defined as ‘the appearance of unfavorable symptoms after exposure to the pollen present in the atmosphere‘. This is a very common pathology, and according to data from the Spanish Society of Allergology and Clinical Immunology (SEAIC) it affects more than 8 million people just in Spain.

What causes a pollen allergy?

Pollen allergy and the immune system
Antibodies are an important part of this reaction.

In general terms, an allergy is a hypersensitivity reaction that a person has to certain substances known as allergens. These substances have the particularity of being harmless in healthy people, affecting only sensitive people.

Repeated contact with allergens stimulates the production of specific antibodies called immunoglobulins E (IgE). These antibodies will bind to the surface cells in the immune system called mast cells, which will secrete large amounts of histamine when they come into contact with a specific allergen.

Histamine secretion will be responsible for the appearance of various allergy symptoms, especially inflammatory processes. It is important to know that not all pollen produces allergies. In fact, for it to be considered an allergen it must meet the following characteristics:

  • To be light
  • To be produced in abundant quantities.
  • The plant that produces it must have a wide local distribution.
  • It must have a size of between 5 and 60 micrometers.

What plants cause the allergy?

The main etiological agents of the disease may vary depending on the geographic location and the native flora of the area. In this sense, studies have determined that the most common cause of pollen allergy in Europe is pollen from grasses, that is, plants such as wheat, corn and rye.

On the other hand, there are other very widely distributed plants capable of producing pollen that produces pollinosis. In this sense, the disease can also originate from the action of the following plants:

  • Olives
  • Cypress trees
  • Chenopodium album or ashes
  • Birches
  • Parietaria
  • Artemisias and ragweed


One of the main entry points for pollen to the body is through the respiratory tract, which is why most manifestations of the pathology occur at this level. In this sense, allergic rhinitis is the most common form, and so patients may report some of the following symptoms:

  • Nasal congestion
  • Frequent sneezing
  • Itching in the nose or throat
  • Runny nose
  • Dyspnea (respiratory distress) and asthma in the most severe cases

For its part, pollen can also come into contact with the conjunctiva and cause the appearance of symptoms at this level. This condition is known as allergic conjunctivitis, so patients may experience itchy eyes, red eyes, and constant tearing. Some people also have general symptoms, including the following:

How do you make the diagnosis?

A person’s medical history is usually the only tool necessary to make the diagnosis of pollen allergy. The presentation of symptoms is related to the seasons of the year, being more frequent during spring and summer. The specialist may ask about the appearance, duration and intensity of the symptoms to make an accurate diagnosis.

If you want to determine the specific type of pollen you’re allergic to, then your doctor may order a skin test or prick test. This type of test consists of inoculating the skin with a small amount of the allergen, and, after a few minutes, a small lump should be observed in the injection area in case of there being a positive result.

The characteristic raised area after the prick test is due to the inflammatory reaction that the substance produces in the body. It’s also possible to quantify the amount of IgE present in the blood for a certain allergen known to the patient.

Pollen allergy treatment

Pollen allergy treatment
Oral antihistamines are one of the most widely used options.

As with all allergies, the main treatment available is prevention and not being exposed to the allergen. However, this is very difficult when it comes to pollen, as it’s in the air for many months of the year. In this sense, it’s best to treat the symptoms when they appear.

The use of a class of drugs called antihistamines has been shown to be very useful in treating the symptoms of pollen allergy. They antagonize histamine, preventing it from fulfilling its effect on the tissues and preventing the appearance of respiratory and ocular symptoms.

Nasal decongestants and eye drops are also useful in eliminating symptoms, since they reduce the contact between the allergen and the mucosa. At present, a kind of vaccine has been developed for pollen allergy known as immunotherapy, which consists of reducing sensitivity to the substance.

Generally speaking, in immunotherapy, increasing doses of the allergen are administered to the patient in order for the body to create antibodies that capture the substance before it interacts with IgE in mast cells. However, studies show that not all patients are suitable for this process and should be evaluated by an allergist.

Pollen allergy prevention

As previously mentioned, avoiding being in contact with pollen is almost impossible during certain months of the year. However, people can take certain measures to reduce exposure and avoid the appearance of characteristic symptoms. In this sense, people with a pollen allergy can follow the following tips:

  • Avoid going out on hot, dry, and windy days: all these conditions help spread pollen in the environment. The ideal thing is to go out on the coldest and cloudy days to reduce exposure.
  • Keep windows closed: pollen can easily enter any area, and so it’s recommended that you don’t open your windows too wide. It’s also advisable to travel by car with the windows closed and with the air conditioning on.
  • Limit outdoor activities: The concentration of pollen in the air may be higher on some days than on others. In this sense, it’s recommended not to do any type of outdoor activity on days with high pollen concentrations.
  • Change clothes when you get home: pollen adheres very easily to all types of fabrics, especially cotton. The best option to avoid symptoms in the comfort of home is to remove your clothes and take a shower after you go out.
  • Wear goggles and a protective mask: People with severe allergy symptoms should wear sunglasses and protective masks before going out. This measure becomes more important when the atmospheric concentration of pollen is high.

A frequent and uncomfortable pathology

Pollen allergy is a condition that affects millions of people around the world. It can be caused by a large number of different plants, although the most frequent etiological agent is usually grasses.

Its symptoms appear within a few minutes of being in contact with the allergen and affect the respiratory tract and eyes. The pathology in question is very annoying and greatly affects the lives of those who suffer from it, as it limits the performance of outdoor activities at certain times of the year.

When symptoms start to appear, then it’s important to go to the doctor. Only the specialist will be able to indicate the most appropriate treatment. In addition, they can provide instructions to minimize the impact of the allergy on daily life.

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