Pollen allergies, such as tree pollen allergies, are caused by the chemical histamine which is responsible for most symptoms of pollen allergies. Histamine is released as allergens and transmitted to the mast cells for destruction.
Some symptoms of pollen allergies are a runny nose, sneezing, coughing, itchy nose, throat and roof of mouth, watery or itchy eyes as well as sinus pressure. Some individuals with pollen allergies may also experience a reduced sense of smell and taste.
Tree pollen allergies may also react with protein of certain foods that you eat and may cause oral allergy syndrome. This happens when your body confuses some foods such as vegetables, fruits or nuts with tree pollen to which you are allergic to. This pollen allergy syndrome may result into itching or swelling around your mouth as well as tingling while eating a particular foods.
Pollen allergy is said to have caused allergic rhinitis. Allergic rhinitis symptoms are due to the response of our body to pollen we have inhaled. Inhaling pollen causes chronic inflammation of the nasal passages and of your eyes and may also cause itchy ears, throat and palate.
Pollen can also trigger asthma as well as allergic rhinitis or hay fever since small pollen particles can even penetrate the deepest part of your lungs and can cause wheezing particularly during spring. Hay fever may be accompanied by excess fluid or mucus release. The red and itchy eyes as symptoms come about just like how your nose reacts to the allergens. Your eyes may turn red and itchy, eventually producing a lot of tears. These reactions are considered defense reactions against the allergens.
Other symptoms of pollen allergies include swollen eyelids, wheezing and difficulty in breathing particularly if you have asthma. People with asthma and who inhale pollen allergens suffer from a condition by which their airways become narrow making it harder for air to enter their lungs. This difficulty in breathing is accompanied by the wheezing or whistling sound while breathing. A feeling of tightness in the chest can also be experienced.