Pollen are the microspores of seed plants such as grasses, ragweed and trees that insects and the wind transport in the process of fertilization. Individuals who are sensitive to pollen might be exposed by inhaling the spores or react to the injections of the material meant to desensitize an allergic individual.
Only a few species of various plants that bear seeds can trigger allergic reactions. The potential effects of pollen can vary from minimal irritation to shock and death.
One common effect of pollen shots for treatment or tests is swelling of the site. The minor puffiness and redness at the site is prevalent and not an issue of concern unless it lasts more than 24 hours or grows more than 4-5 centimeters in diameter.
In case the swelling and redness is evident, it can cause discomfort and must be treated with antihistamines and the application of a cool compress. The swelling is a warning sign to lower the dosage before a reaction becomes dangerous.
A common side effect that arises after inhaling pollen is sneezing. It is important to note that sneezing might be followed by itchy eyes, runny nose and a scratchy throat. These reactions are triggered by the production of histamine which causes the dilation of the small blood vessels in the nose and makes the nasal passages swollen and congested.
Even though most react to the ingestion of pollen by forming mucous around the offending particles and moving them down the throat to be swallowed or coughed out, some who are allergic react with nasal congestion, sneezing and irritated throat or eyes.
Among those who are sensitive to plant pollen in the air and respond with seasonal allergy symptoms, the condition can become chronic and progress to asthma.
Irritated eyes and throat as well as sneezing can turn into a serious condition with wheezing, coughing and difficulty breathing. The bronchial passages also become constricted where excess mucus is generated, and the bronchial tubes are irritated until infected.
A serious side effect of pollen injection is anaphylaxis. Allergy skin tests and immunotherapy can lead to the closure of the breathing passages which requires immediate care with a shot of epinephrine.