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Hay Fever
What is Hay Fever? Hay fever is a type of allergic rhinitis caused by pollen or spores. The allergen causes the inside of the nose to become inflamed. Hay fever affects the nose, sinuses, throat and eyes and causes sneezing, a runny nose, and itchy eyes.
The symptoms of hay fever occur when the immune system overreacts to a normally harmless substance, in this case pollen. When the body comes into contact with pollen, cells in the lining of the nose, mouth and eyes release histamine, which triggers the symptoms of an allergic reaction. Hay fever usually occurs in spring and summer, when there is more pollen in the air. Trees, grass and plants release pollen as part of their reproductive process. Mould and fungi also release tiny reproductive particles, called spores. People with hay fever can experience their symptoms at different times of the year, depending on which pollens or spores they are allergic to. Hay fever is estimated to affect around 20% of people. Hay fever is more likely if there is a family history of allergies, particularly asthma or eczema. In Ireland, most people with hay fever are allergic to grass pollen. However, trees, mould spores and weeds can also cause hay fever. Research suggests that pollution, such as cigarette smoke or car exhaust fumes, can make allergies worse.
Treatments
Hay fever cannot be cured completely, but there are a number of treatments available to relieve the symptoms.
Oral Antihistamines
Two types of OTC antihistamines are available: first-generation and second-generation antihistamines. Both types can be useful for allergies. First-generation antihistamines are also sometimes used in OTC cold medicines
First-generation antihistamines work in the part of the brain that controls nausea and vomiting. They can also help prevent motion sickness and are sometimes used to help insomnia. The most common side effect of firstgeneration antihistamines is feeling sleepy. They may also cause symptoms such as dry mouth, urinary retention and confusion in the elderly. Types of first-Generation OTC Antihistamines: • Brompheniramine • Chlorpheniramine • Dimenhydrinate • Diphenhydramine • Doxylamine
Second-generation or non-sedating
antihistamines are newer drugs. They offer the advantages of a lack of side effects such as sedation and dry mouth, which are commonly seen in first-generation antihistamines. Secondgeneration antihistamines are less likely to interact with other medicines. Their longer duration of action also enables a more patient-friendly dosing regimen which increases patient compliance. Types of second generation antihistamines • Loratadine
• Cetirizine
• Fexofenadine
Ocular antihistamines
OTC Eye drops treat the hay fever symptoms that affect the eyes, such as redness, itchiness and watering (allergic conjunctivitis). These drops contain antihistamine to reduce the inflammation in the eyes, which will relieve the symptoms. Eye drops containing the active ingredient sodium cromoglicate are the most widely used. Some may cause side effects, such as a stinging or burning feeling in the eyes.
Corticosteroids
If symptoms are frequent or persistent and individuals have nasal blockages or nasal polyps, a nasal spray or drops containing corticosteroids should be recommended. Corticosteroids help to reduce inflammation. They take longer to work than antihistamines but their effects last longer. Side effects from inhaled corticosteroids are rare but can include nasal dryness and irritation, and nosebleeds.
Nasal decongestants
Decongestants can be taken as tablets, capsules, nasal sprays or liquids. They should not be used to treat allergic rhinitis for more than five to seven days. Using them for longer can worsen congestion. They are not recommended for those taking a type of antidepressant known as a monoamine oxidase inhibitor (MAOI).
Non-pharmacological Treatment
Non-pharmacologic management may provide symptomatic relief and reduce the need for medications in patients, particularly those who are affected seasonally. Guidelines developed in collaboration with the World Health Organisation recommend: • The identification and avoidance of allergens when practical. However, the evidence does not suggest that any one intervention alone will lead to substantial symptom reduction. • Recommendations have included the minimisation of exposure to pollen or mould, which are major allergens for patients with seasonal rhinitis, by keeping windows and doors closed during pollen season. • Outdoor activities should also be minimised on sunny days with low humidity and high winds, as pollen counts tend to increase on those types of days. • For patients with indoor allergies, such as sensitivity to dust mites, methods to reduce exposure include reducing the use of carpets, maintaining a level of humidity between 35% to 50%, washing the bedding in hot water, avoiding stuffed toys and upholstered furniture, and placing mattresses and pillows in allergy-proof coverings.
WWho: A global health problem affecting 20% of the population
WWhat are the symptoms? Runny nose, watery eyes, sneezing, itching
HHow long have they had symptoms? Symptoms may last for weeks
or months
AAction already taken? Sufferers may already be implementing lifestyle
changes or have tried OTC treatments
MMedication: Refer to a GP for first-generation antihistamines if the
