22, Fév 2022
With the early spring shoots the manifestation of some characteristic symptoms of seasonal allergies. There are several types of allergies caused by different allergens and that manifest differently, too. The manifestation of some symptoms, within a certain period of the year, features seasonal allergies. Typically, spring allergies are caused by pollens while allergens such as dust mites, are responsible for allergies that occur throughout the year. There are pollens in atmospheric air throughout the year, but in the spring the concentration is significantly higher. In spring and summer there are also other agents that deserve attention, such as insect poison, because they can cause severe allergic reactions, in rare cases even fatal.
In summer the high temperatures and the changes of environment and habits with the holidays provide the appearance of hives, as solar urticaria. For this reason it is important to use sunscreens and taking antihistamines when advised.
In Portugal the main cause of allergy to pollens are grasses (Hay), which reach their peak usually during the months of May and June. The concentration of pollens in the air depends on the pollination and varies for each plant, but coincides for most plants with a spring. The explanation lies in the influence of meteorological variables: the occurrence of rain (previously the pollen season) conditions strong concentrations of pollens when precipitation stops, with hot days and breezy spring; on the contrary, a dry year conditions an opening less intense, in particular pollen of plants are more sensitive to lack of water, such as grasses.
Allergy is an immune system response to a foreign substance to the body. When the immune system senses the presence of foreign elements which it considers dangerous releases a protein called immunoglobulin E (IgE). This protein attaches to the substance that caused the immune alert and promotes release of histamine and other substances. It is mainly the histamine that, in the first few minutes, causes allergic symptoms: sneezing, dyspnea, pruritus, etc.
The symptoms are triggered, in particular outside the buildings, especially in hot, dry and windy weather and condition a lot the quality of life of patients.
Allergy to pollens often causes allergic manifestations of respiratory-asthma and rhinitis, eye-conjunctivitis-or skin-urticaria and eczema).
Allergic rhinitis is the most common allergy. It can reach up to 1/3 of the Portuguese population and is characterized by the occurrence of sneezing, stuffy nose and itchy nose. These symptoms may be accompanied by allergic conjunctivitis (red eye, tearing, itching and swelling).
It is also equally frequent asthma, which causes difficulty in breathing, wheezing, and coughing, tiring easily and the hives and eczema, that cause symptoms of skin.