Spring brings with it the awakening of nature, but for millions of people, it also represents the beginning of a season of discomfort and suffering. Spring allergies, or “pollinosis,” affect approximately 20-30% of the Italian population, with an incidence that has been steadily increasing in recent decades, partly due to pollution and climate change.
In this article, we will explore everything you need to know about pollinosis: from the biological mechanisms that cause it to the characteristic symptoms, from preventive strategies to the most effective therapeutic options.
What is pollinosis and how does it develop
Pollinosis is an allergic reaction triggered by exposure to the pollen of plants, trees, and grasses. It is an inappropriate immune response, in which the body’s defense system mistakenly identifies normally harmless substances (the allergens contained in pollen) as dangerous.
The mechanism underlying pollinosis develops in several phases:
- Sensitization: first contact with the pollen allergen leads to the production of specific antibodies (immunoglobulin E or IgE) that bind to mast cells, immune system cells present in tissues.
- Effector phase: in subsequent contacts, the allergen binds to IgE on the surface of mast cells, causing the release of inflammatory mediators, including histamine. These mediators are responsible for the typical symptoms of allergy.
- Chronic inflammation: repeated exposure can lead to persistent inflammation of the mucous membranes, increasing their reactivity even to non-allergenic stimuli (hyperreactivity).
It’s important to emphasize that there is a genetic predisposition to allergies: those with allergic parents have a significantly higher probability of developing allergies themselves, although not necessarily to the same allergen.
Symptoms of pollinosis: not just sneezing
Symptoms of pollinosis vary in intensity and combination from person to person, but typically include:
Nasal symptoms (allergic rhinitis)
- Frequent sneezing, often in bursts
- Intense nasal itching
- Rhinorrhea (runny nose) with watery and abundant secretion
- Nasal congestion, sometimes alternating between the two nostrils
- Reduced sense of smell
Eye symptoms (allergic conjunctivitis)
- Conjunctival redness
- Intense eye itching
- Excessive tearing
- Sensation of a foreign body or “sand in the eyes”
- Photophobia (discomfort in light)
- Eyelid swelling
Respiratory symptoms
- Dry cough, especially at night
- Wheezing
- Sense of chest tightness
- In asthmatic subjects, possibility of asthma attacks
General symptoms
- Fatigue and reduced concentration
- Sleep disturbances
- Irritability
- Headache
- Rarely, skin rashes
An important aspect to consider is the “allergic march,” or the tendency of allergic manifestations to evolve over time. Many children start with atopic dermatitis in the first years of life, subsequently develop food allergies and allergic rhinitis, and in some cases progress to asthma. This progression underscores the importance of early diagnosis and adequate treatment.
How do I distinguish pollen allergy from a cold?
The distinction between pollen allergy and other respiratory conditions can sometimes be difficult, but some elements can help in the differential diagnosis:
Allergy vs. Common Cold
- Allergy persists as long as there is exposure to the allergen (weeks or months), while a cold generally lasts 7-10 days. Allergic symptoms appear rapidly after exposure, cold symptoms gradually.
- Nasal secretions are watery and clear in allergy, thicker and yellow-greenish in a cold.
- Allergy shows much more often itching and an absence of fever, while in a cold it is often the opposite. Moreover, seasonality leads the allergy to present itself always in the same period, while a cold depends on contagion.
When should I suspect a pollen allergy?
A correct diagnosis is fundamental for setting up effective therapy. The ideal time for diagnosis is outside the pollen season, when symptoms are quiescent, but tests can be performed at any time of the year.
Symptoms to pay attention to are:
- Respiratory symptoms that recur in the same period every year
- Worsening of symptoms outdoors, especially on windy and sunny days
- Improvement in closed and air-conditioned environments
- Association with other allergic conditions (atopic dermatitis, asthma)
Here’s how to make a correct diagnosis.
Naturally, you will need a doctor to help you understand what your problem really is. The doctor will gather detailed information about symptoms, their periodicity, triggering factors, and family history.
Then they will make an assessment of the nasal mucosa, eyes, and respiratory system.
They might then propose that you do the following tests:
- Prick test: consists of applying small amounts of allergenic extracts to the skin of the forearm or back, followed by a light superficial prick. In case of sensitization, an itchy wheal develops within 15-20 minutes.
- Serological tests: measurement in the blood of specific IgE towards individual allergens (RAST, ImmunoCAP, ISAC). Useful when skin tests are not feasible or in case of doubtful results.
- Nasal provocation test: rarely necessary, consists of direct application of the allergen to the nasal mucosa to verify the response.
Pollen-food syndrome
An important aspect to consider is the possibility of cross-reactions between pollens and plant foods. This phenomenon, known as pollen-food syndrome, occurs when antibodies produced against pollen allergens also recognize similar proteins present in fruits, vegetables, or nuts.
Some common associations include:
- Birch allergy → reactions to apple, peach, hazelnut, carrot, celery
- Grass allergy → reactions to tomato, melon, watermelon, kiwi
- Artemisia allergy → reactions to celery, carrot, spices
- Parietaria allergy → reactions to basil, melon, cherry
Symptoms are generally limited to the oral cavity (itching, swelling of lips and tongue) and appear immediately after consuming the raw food, while cooking often inactivates the allergens.
How do I prevent symptoms?
Prevention represents the first step in managing pollen allergies. Reducing exposure to allergens can significantly decrease symptoms and the need for medications. Here are some effective strategies:
Monitoring pollen levels
- Consult websites that update on pollen levels
- Plan outdoor activities on days with lower pollen concentration
- Remember that pollen levels are generally higher in the early morning and on windy and sunny days
Changes in the home environment
- Keep windows closed, especially during peak pollination hours
- Use air conditioners with adequate filters, cleaning them regularly
- Consider using air purifiers with HEPA (High Efficiency Particulate Air) filters
- Avoid hanging laundry outside during the pollen season
- Clean surfaces frequently with damp cloths to remove deposited pollen
- Regularly wash curtains and upholstery fabrics that can trap pollen
Personal precautions
- Wear sunglasses outdoors to protect the eyes
- Consider using masks when pollen levels are particularly high
- Change clothes after being outdoors and wash them before putting them back in the wardrobe
- Shower and wash hair before going to bed to remove pollen accumulated during the day
- Avoid keeping flowering plants in the house
- Limit outdoor activities on high-risk days, especially sports or gardening
Pharmacological treatment of pollen allergies
Therapeutic options for pollen allergies are multiple and can be adapted to the specific needs of each patient. A personalized approach is essential, considering the severity of symptoms, the patient’s age, and the presence of any comorbidities.
Antihistamines
Antihistamines represent the first line of treatment for most patients. They act by blocking histamine receptors, thus attenuating allergic symptoms, particularly sneezing, rhinorrhea, and itching.
Corticosteroids
Corticosteroids are effective in reducing inflammation of the mucous membranes and are particularly indicated for nasal congestion, a symptom that responds less to antihistamines: remember that they should always be prescribed by a doctor.
Specific immunotherapy: the “vaccine” against allergies
Specific immunotherapy (SIT), also known as the “anti-allergy vaccine,” represents the only treatment capable of modifying the natural course of allergic disease, rather than merely controlling its symptoms.
How it works
SIT consists of the gradual and progressive administration of the allergen to which the patient is sensitized, with the goal of inducing immune tolerance. The mechanisms of action include:
- Modification of T lymphocyte response towards an anti-inflammatory profile
- Induction of regulatory T cells
- Reduction of specific IgE production and increase of blocking IgG
- Decreased release of mediators from mast cells and basophils
Duration and efficacy
The standard duration of treatment is 3-5 years, while clinical benefits can begin to manifest after just 3-6 months. The efficacy generally persists for years after the conclusion of treatment, while studies show a reduction in symptoms and drug consumption of 30-40% compared to placebo.
It should always be performed under medical supervision, even though it is considered a safe therapy.
And during pregnancy?
Managing pollen allergies during pregnancy requires a careful balance between controlling maternal symptoms and safety for the fetus:
- Second-generation antihistamines, particularly loratadine and cetirizine, are considered relatively safe after the first trimester
- Nasal corticosteroids represent a good option to minimize systemic exposure
- Immunotherapy should not be started during pregnancy, but can be continued if already in progress and well tolerated
- Nasal washes with saline solution are particularly useful, being free of side effects
We are with you
At Parentalife, we are by your side in the journey of raising your children. We support you with practical guides, training courses, and with personalized consultations.
Remember, we are with you.
SOURCES
1. D’Amato G, et al. “Climate change, air pollution and extreme events leading to increasing prevalence of allergic respiratory diseases.” Multidisciplinary Respiratory Medicine. 2013;8(1):12. DOI: 10.1186/2049-6958-8-12.
2. Cecchi L, D’Amato G, Ayres JG, Galan C, Forastiere F, Forsberg B, Gerritsen J, Nunes C, Behrendt H, Akdis C, Dahl R, Annesi-Maesano I. Projections of the effects of climate change on allergic asthma: the contribution of aerobiology. Allergy. 2010 Set;65(9):1073-81. doi: 10.1111/j.1398-9995.2010.02423.x. Epub 2010 Giu 17. PMID: 20560904.