Grass pollen allergy — technically allergic rhinitis caused by Poaceae pollen — is by far the most common pollen allergy in Croatia and Europe. It is estimated that around 10–15% of the population has pronounced sensitivity, and an even larger percentage experiences milder symptoms.

What are "grasses"

The term "grasses" encompasses more than 9,000 species in the Poaceae family, but only about a dozen matter for allergy sufferers — and they share common allergenic proteins, making it rare to be allergic to just one grass species. The most important for our region:

  • timothy grass (Phleum pratense) — reference species in diagnostics
  • perennial ryegrass (Lolium perenne)
  • orchard grass (Dactylis glomerata)
  • tall fescue (Festuca pratensis)
  • bentgrass (Agrostis)

Cereals (wheat, oats, rye, barley) also belong to Poaceae and can produce pollen, but their heavier pollen and shorter flowering period make them less problematic.

Season

In Croatia, grass pollen season lasts from mid-May to the end of July, with peak levels in June. Along the coast it begins 1–2 weeks earlier, and in mountain regions (Lika and Gorski kotar) it starts later. The season is shorter than ragweed season, but daily peak concentrations are often higher.

The worst days are dry, windy with temperatures of 20–25 °C — ideal conditions for pollen dispersal. Rain significantly reduces concentrations but intensifies flowering in the following days.

Typical symptoms

  • nasal irritation, sneezing in fits, watery discharge;
  • nasal congestion, especially at night;
  • red and watering eyes, itching;
  • itching in the throat and palate;
  • fatigue, poor concentration, "brain fog";
  • in 30–40% of grass allergic patients, allergic asthma develops with cough and wheezing.

Many patients describe marked worsening 2–3 days after lawn mowing in parks and near apartment buildings.

Cross-reactions with food

Proteins from grass pollen are related to proteins in some fresh plants, and in sensitive individuals can trigger oral allergy syndrome:

  • tomato — most common cross-reaction (itching and mild swelling of mouth)
  • kiwi, peach, watermelon
  • peanuts and soy in some individuals

Reactions are usually mild and localized to the mouth. Cooked versions of the same food (tomato sauce, jam) are usually well tolerated.

What works — steps

1. Avoidance

Completely avoiding pollen outdoors is impossible, but several measures noticeably reduce exposure:

  • Do not mow the lawn yourself during the season; wear a mask if you must.
  • Ventilate in the morning before 9 am or late in the evening.
  • Keep car windows closed, use pollen filter if available.
  • Wash hair before bed and do not dry laundry outside.

2. Over-the-counter medications

  • Second-generation antihistamines (cetirizine, loratadine, levocetirizine, fexofenadine) — foundation of therapy. Take regularly throughout the season, not just when it's already bad.
  • Nasal corticosteroid sprays (mometasone, fluticasone) — most effective for nasal congestion. They need 5–10 days of regular use for full effect; do not "save them" for the worst days.
  • Eye drops with antihistamine or cromolyn.
  • Saline rinse before and after going outside.

3. Immunotherapy

Specific immunotherapy (SIT) is the only therapy that changes the course of disease, not just symptoms. For grass allergy, it is available in two forms:

  • Subcutaneous immunotherapy (SCIT) — injections at an allergist's office, initially weekly, later monthly.
  • Sublingual immunotherapy (SLIT) — drops or tablets under the tongue, daily.

Treatment lasts 3–5 years and is usually started 3–4 months before the season. Efficacy is well documented by scientific research — in most patients it significantly reduces symptoms and medication needs, and benefits persist after therapy ends.

Candidates for immunotherapy are patients whose symptoms:

  • last more than 3 months per year,
  • do not respond satisfactorily to over-the-counter medications,
  • have significant impact on daily life,
  • have pronounced eye involvement or develop asthma.

Talking with your family physician and getting a referral to an allergist are the first steps.

When to see a doctor

  • if symptoms last longer than a month with severe intensity
  • if you experience shortness of breath, wheezing, or chest tightness
  • if over-the-counter medications do not help despite regular use
  • if you are considering immunotherapy or diagnostic tests

Note

This is not medical advice. For specific recommendations and assessment of immunotherapy suitability, consult your family physician or allergist.