Pollen Allergy or Hay Fever Authored by DesiMD Doctor
Introduction The word pollen is derived from Greek which means 'fine flour'. The pollen grains are produced in a flower to fertilize the stigma or female flower to produce seeds. The quantities of pollen grains produced are different for different species of plants. The pollen grains produced in small numbers are distributed by bees, birds and other insects from one plant to another, while some plants depend on the wind to disperse the pollen grains. Some plants produce pollen in large quantities and are dispersed by the wind to long distances. This is the main cause of pollen allergy. Pollen from weeds, grasses and trees trigger the symptoms of allergy. Pollen can cause allergic rhinitis (hay fever) and asthma. The season for production of pollen grains usually last for long periods which increase the chances of getting exposed to them. Causes Pollens causing allergic rhinitis:
It is commonly called as hay fever. This allergic reaction is caused when the immune system of the body responds to the inhaled pollen grains which results in developing the symptoms of allergic rhinitis. One in five people develop allergic rhinitis due to pollen allergy. Pollens causing asthma: Pollen grains can directly cause asthma besides causing allergic rhinitis. The small particles of pollen which contain allergen can directly penetrate deep into the lungs which trigger asthma. This is usually caused when the pollen grains come in contact with water during storms. When the pollen comes in contact with water they release small starch granules which can be breathed easily into the airways causing asthma or allergic rhinitis. Symptoms The symptoms of pollen allergy start as soon as the body responds to the invaded pollen grains. The symptoms include: • Nasal congestion • Sinus pressure which may cause facial pain • Watery and itchy eyes • Runny nose • Cough • Puffy, bluish skin beneath eyes • Scratchy throat and palate • Reduced sense of smell or taste • Sneezing Diagnosis First a careful history should be noted to confirm that it is pollen allergy. It can be done by taking a note of the timing of symptoms, identifying the trees and plants which are present in surrounding areas and checking whether the symptoms reduce on staying away from that place. When it is suspected as pollen allergy, further confirmatory tests can be carried out. These tests include skin prick test and blood allergen specific IgE test. These tests along with the history noted can help the physician to diagnose the allergy precisely.
Treatment The following classes of drugs are used in the treatment of pollen allergy: • Antihistamines: These drugs are given to help reduce sneezing, itchy eyes and dermatitis. They are available as tablets and syrups and also have the advantage of flexibility meaning that they can be taken only when symptoms persist and stop them when symptoms subside. The drawback is that they are poor in controlling nasal congestion. Antihistaminic eye drops are also available which can be used to reduce eye symptoms.
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Combination drugs: These drugs contain both antihistamine and a decongestant. These drugs need to be used with caution as they can cause side effects.
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Intranasal corticosteroid sprays: these sprays are used to reduce the intranasal symptoms. They are to be used regularly if asthma is caused due to pollen allergy.
Decongestant sprays: These are used to help unblock and dry the nose, but should not be used for many days as they can cause long term problems in the nose. They can have side effects such as tremors, insomnia, anxiety or increased blood pressure. They should not be used by people with hypertension. Immunotherapy: This is a long term treatment option. The drug therapy can only reduce the symptoms for the time being but cannot completely cure the allergy. Immunotherapy cures the allergy completely by switching off the allergic reaction to the pollen grains. It is done by injecting small doses of the specific allergen in to the body to make the body get used to it. This therapy is given over a period of few years. Prevention •
The following tips should be followed to reduce the exposure to pollen: • Avoid going outdoors in the morning as pollen is widespread at that time • Wear sun glasses to protect the eyes • Avoid going outside on windy days or after storms • Do not mow the grass yourself and stay indoors when it is being done. Wear a mask if it has to be done by you. • Do not go on picnics during the pollen season • Keep the windows of the car and home closed • Take a shower immediately after coming back home • Wash your eyes frequently with fresh water