The allergenic plants, or the plants that cause allergies, are a problem for more and more people.
A European survey found that about 1 in 4 citizens are now suffering from allergies and, according to the Ministry of Health, allergic rhinitis (with or without conjunctivitis) affects 60% of the European population.
According to ISTAT data, allergies are the third cause of chronic disease in Italy after osteoporosis / arthritis and hypertension.
In this article you will find a list of allergenic plants to watch out for, indications of allergy symptoms, the most dangerous periods for different plants, tips for limiting negative effects and some possible remedies.
Allergenic plants: what are they
Allergenic plants are plants whose pollen can cause allergies in predisposed individuals. Allergies therefore do not develop towards “the whole plant” but towards the pollen that the plant releases during the flowering period. For this reason, in addition to determining the type of plant to which you are allergic, it is important to know the periods in which the plants bloom, following special calendars on specialized sites.
The three main groups of allergenic pollen can be issued by:
- Grasses, such as chaff, fleece, mazzolina grass, weeds and cotton wool
- Herbs like theambrosia and themugwort
- Plants such as hazel, ash, alder, oak, hornbeam, hornbeam, beech and birch
The grasses (opening photo of this article) are the main pollen allergen and are the leading cause of pollen allergies in Italy. About 20% of the population, equivalent to 1 in 5 people, is allergic to it.
The grasses they produce a lot of pollen and for a long period since flowering occurs for cycles of several months during the year. They are also very widespread throughout our country.
The flowering of the grasses generally occurs from April to the end of August, with the maximum intensity between May and July.
Due to climate change, however, the flowering period in Italy is extending, creating problems for longer periods for those who are allergic to it.
It is widespread in the countryside, in the hills or in the mountains, but is also spreading to the plains.
L'ambrosia (as a scientific Ambrosia artemisiifolia) is the second most important cause of allergy in Italy. His pollen is highly allergic, carrying burning eyes, dry throat up to asthma in the most sensitive subjects.
L'ambrosia it is increasingly widespread in the plains, on dry land, flower beds, fields and abandoned land. It can also grow on soils with high salt concentration and low nutrients.
However, it is not widespread above 1200 meters above sea level.
L'ambrosia blooms in the month of August, but it can also bloom from June to mid-September.
Ambrosia, an allergenic plant that is increasingly widespread in Italy
Despite its use in herbal medicine and in Chinese folk medicine,mugwort (as a scientific Artemisia Vulgaris) is another herb whose pollens are highly allergenic.
L'mugwort belongs to the Composite family, plants that grow mainly in the hills but also in the plains, near rivers and streams.
The period of peak of the flowering of mugwort in Italy is in the months of August and September.
In allergy sufferers it causes sneezing, runny nose, red eyes and dry throat.
An inflorescence of Artemisia, an allergenic plant Image source: Mitel - University of Udine
THE plant pollen such as hazel, ash, alder and the birch in particular they can create allergies to predisposed subjects but have mainly local effects. Pollen does not spread over large areas and is therefore less of a concern.
Nevertheless, in the cities, in order to avoid potential allergies to the inhabitants, attention is also being paid to the type of plant and correct distribution within the parks.
What are the symptoms of allergies to Ambrosia, Artemisia or Grasses
Symptoms of allergies to Ambrosia, Artemisia, Grasses and other plants are:
- burning in the eyes
- a runny nose
- dry throat
- sleep disorders
How to tell if you are allergic to Ambrosia, Artemisia or Grasses
One of the clues is the occurrence of one or more of the symptoms just mentioned in correspondence with the flowering period of the different herbs and plants.
To dispel any doubt it is possible to perform two types of tests:
- The "Prick test", An allergy test that involves the application of small amounts of allergens on the forearm to then monitor the onset of skin manifestations that indicate sensitivity to the substances tested;
- The "Rast Test“, A serological test for the detection of IgE immunogammaglobulins responsible for the allergic reaction.
These tests can be done in hospitals or specialized practices.
Because our body generates an allergic response to grasses, ragweed or mugwort
Allergic manifestations are the consequence of a reaction of the immune system which is activated by mistakenly identifying pollen as dangerous substances for our body.
The production of antibodies, immunoglobulins, stimulates some immune cells, mast cells, to release histamine, a substance that promotes inflammation. From this mechanism derive allergic reactions that can occur below with the symptoms listed above.
How to limit allergic reactions to allergenic plants
To limit the annoying symptoms of allergies to allergenic plants we can try to implement the following countermeasures during the pollen season:
- In general, in the city, try to stay away from parks and areas where allergy-causing plants grow (especially in the morning, when pollen is most present in the air)
- Air the rooms for shorter periods and use an air purifier with a pollen filter (you will find several to choose from on this page with prices starting from 70 Euros to 300 Euros for good quality products)
- Avoid hanging clothes outdoors (as pollen could stick to the clothes you will later wear)
- Use a mask with suitable pollen filters (here you will find different types)
- Wear sunglasses to avoid eye contact with pollen
- Spend a few days at the sea where pollen is less present
- Clean furniture, sofas and carpets more regularly
- Wash your hair before going to bed (to avoid carrying pollen on the pillow)
- Stop smoking or otherwise try to limit the consumption of cigarettes and passive smoking
- Avoid foods that can potentiate the allergic reaction (see last paragraph of this article)
To precisely identify the flowering periods of allergenic plants in relation to your area of residence, you can consult the pollen calendars available online or pollen bulletins. To this end, I recommend that you visit the official website ofAIA, Italian Association of Aerobiology.
Medicines to combat pollen allergies
If the countermeasures we have listed do not resolve or sufficiently alleviate your allergy, you can contact your doctor to prescribe specific drugs.
On the authoritative's website Humanitas Research Hospital, highly specialized hospital, research center and university teaching center, the following drugs are noted:
- Bronchodilator drugs and corticosteroids to be nebulized through spray dispensers or to be taken as tablets orally.
- Antihistamine drugs, histamine receptor antagonists that block histamine production and relieve most of the symptoms of allergies, especially itching, sneezing and watery eyes.
- Nasal decongestants spray.
- Sodium cromoglycate and antileukotrienics, a class of drugs for oral use that can help relieve the symptoms of rhinitis in a short time
If you are looking for a long-term solution to your allergy, you will need to undergo a long-term treatment (from 3 to 5 years) which includes desensitizing therapy or specific immunotherapy with allergenic extracts.
Relationship between pollen allergies of allergenic plants and nutrition: which foods to avoid
Several studies have proven a possible increase in allergic symptoms following the intake of foods belonging to the same families as allergenic plants.
For example, those allergic to mugwort should avoid eating celery, fennel, chamomile and pumpkin during the peak flowering period.
Those allergic to grasses should avoid melon and those allergic to ragweed should avoid bananas, watermelon, zucchini and cucumbers.
Those allergic to birch should avoid pears and apples.