Giant Ragweed, W3

Ragweed (Ambrosia) is a genus of herbaceous plants or shrubs and is considered a potent allergen. It grows in fields as well as in neglected areas on the outskirts of cities. Ragweed pollen dispersal occurs from late summer to early autumn, which is when allergic symptoms typically develop.

Ragweed allergy occurs when a small amount of pollen is inhaled and enters the respiratory tract. The body perceives this seemingly harmless pollen as a foreign substance that must be eliminated. As a result, an immune response is triggered to destroy the “invader.” A pollen concentration of fewer than 30 grains/m³ is sufficient to provoke an allergic reaction. Moreover, in highly sensitive individuals, symptoms may occur even at 1–2 pollen grains/m³.

Allergen w3 (Ambrosia trifida, giant ragweed), specific IgE is a diagnostic method for hypersensitivity to pollen allergens of this weed, based on measuring blood levels of allergen-specific IgE antibodies that mediate allergic reactions.

Allergy symptoms
Symptoms of ragweed allergy resemble those of other forms of pollinosis. In patients with bronchial asthma, they can worsen disease control and may cause cough and wheezing. Allergic individuals may experience:

• sneezing, nasal congestion;

• watery nasal discharge (rhinorrhea);

• headache;

• eye irritation;

• throat itching;

• reduced or lost sense of smell;

• drowsiness, chronic fatigue.

In particularly severe cases, ragweed pollen may trigger anaphylactic shock. It has a sudden onset and a severe course, which can lead to airway obstruction and even death.

Diagnostic confirmation
One way to confirm ragweed allergy is a laboratory blood test. Testing a small blood sample can detect ragweed-specific antibodies. If they are present, this indicates an allergy to this weed.

Preparation for testing
To avoid distorting the results of certain tests (glucose, cholesterol, triglycerides), fatty foods, concentrated sweets, and alcohol should be avoided the day before testing. It is also recommended to postpone blood sampling immediately after diagnostic procedures (X-ray, CT, MRI) and physiotherapy sessions, as these may affect the test result.