Hay fever (allergic rhinitis)

What is it?

Hay fever, also known as seasonal allergic rhinitis, is an allergy-related inflammation of the nasal passages, throat and eye membrane (conjunctiva), caused by sensitivity to airborne pollens and molds. These airborne pollens come from various species of trees, grasses, weeds and other plants whose pollens are carried by the wind rather than by insects.

Because different types of pollen trigger symptoms in different people, each person's specific hay fever "season" is fairly predictable and is related to times when their allergy-triggering plant is in bloom. For example, for people who are allergic to tree pollens and who live in temperate North America, symptoms usually are worst from March through May, when trees are blossoming. June and July are peak months for people allergic to grasses, while people with ragweed allergies suffer the worst symptoms from mid-August through October.

Since molds depend on damp, dark conditions, people who are allergic to molds tend to have the least predictable allergy season. They usually find that their symptoms are more related to warm, rainy weather. In the United States, this means summer and fall are peak times.

Hay fever and its sister ailment, perennial allergic rhinitis (a year-round sensitivity to animal dander, dust mites or cockroaches), are most common in people who have a family history of allergies or a personal history of allergy-related conditions, such as eczema and childhood asthma. Although seasonal allergic rhinitis can affect people in all age groups, its symptoms generally peak during childhood and adolescence.

Symptoms

Symptoms of hay fever usually begin before age 30. They typically include:

• sneezing
• itchy and runny nose
• stuffy nose
• red, itchy or watery eyes
• itchy or sore throat.

The congested nose can lead to mouth breathing, and the dripping mucus can cause persistent cough and sore throat. Because hay fever also causes swelling in the sinuses and near the opening of the Eustachian tube (passage that connects the throat to the middle ear), sufferers can develop additional symptoms of secondary sinus infections or ear infections.

Your doctor will ask you about your symptoms, especially about when you have them and whether they occur outdoors or indoors. Your doctor also will ask about your family history of allergies and your personal history of allergy-related conditions, including eczema, hives and asthma.

Diagnosis

Your doctor will make the diagnosis of hay fever based on your allergy history, the timing and appearance of your symptoms and the results of your physical examination. During your physical examination, your doctor will check for signs of inflammation in your eyes, nose and throat. Typically, the lining of the nose is swollen and pale pink or bluish, though it can be red. The doctor often looks for other signs of allergic rhinitis, such as dark circles under the eyes (called allergic shiners), resulting from chronic sinus congestion, wrinkles under the eyes as a result of chronic puffiness around the eyes, and a crease across the nose from frequently wiping it and pushing it upward.

To identify the specific allergen (allergy-triggering substance) that is triggering your hay fever, your doctor may refer you to an allergist, who can do skin testing. In skin testing, a small amount of a specific allergen is scratched, pricked or injected into the skin. Results are available in 10 to 20 minutes.

Expected duration

Blood tests also can be done to measure eosinophils (a type of white blood cell that increases in number during allergy seasons) or levels of IgE, an allergy-inducing antibody. An elevated eosinophil count or IgE level tells the doctor that there is an allergic response, while skin tests provide more specific information about what the person it allergic to. Blood tests are most helpful when skin testing cannot be done, such as when someone has severe eczema.

Although hay fever symptoms can reappear each year when the offending plant begins to bloom, they tend to diminish as you get older. Some people don't develop hay fever until adulthood.

Prevention

You can help prevent attacks of hay fever by reducing your exposure to the suspected allergens. It helps to:

• Stay indoors as much as possible during months when you know that your hay fever symptoms will flare. Remember that pollen counts tend to be highest before 10 a.m. and after sunset, so schedule any outdoor activities for low-pollen hours. Early afternoon usually is best.
• Keep windows closed, especially bedroom windows. Run an air conditioner on hot days.
• While traveling in your car, you should drive with your external vents closed and air conditioning on. Some newer vehicles can be equipped with a high-efficiency air filtration system.
• Minimize activities with heavy exposure to pollens, such as lawn mowing and leaf blowing.
• When planning your garden, choose flowers that are bright and colorful, because these colors usually signal that the plant is pollinated by insects rather than by wind.
• Take a shower or wash your hair before going to bed at night to remove pollen that accumulated during the day.
• Dry clothes inside, either in a dryer or on a line. Clothing drying on an outside line can gather pollen.

Treatment

Although the best way to treat hay fever is to minimize exposure to the allergens, it is almost impossible to completely avoid airborne allergens such as pollen. There are many medicines, both prescription and nonprescription, to treat hay fever and its symptoms. Nonprescription decongestant sprays and pills can be used to relieve nasal congestion. Decongestant nasal sprays can give relief for a few days but they can cause congestion to get worse if they are used for more than three days.

Another nonprescription nasal spray, cromolyn sodium, prevents allergy symptoms by blocking the release of an irritating substance called histamine. Antihistamines are also available in nasal spray and pill form. You may need to work with your doctor to find the specific antihistamine that best relieves your symptoms with the fewest side effects.

Corticosteroid nasal sprays, such as beclomethasone (Beconase, Vancenase), budesonide (Nasonex) and fluticasone (Flonase), are probably the most effective treatment for hay fever and perennial allergic rhinitis. People with seasonal allergies should start the nasal corticosteroid spray a week or two before an expected rise in pollen counts.

Montelukast (Singular) can be used alone or in combination with other medications to treat allergic rhinitis. It is a leukotriene receptor antagonist, which decreases the allergic response in a different way than either antihistamines or corticosteroids. It is taken by mouth once a day. But montelukast is not as effective as corticosteroid nasal sprays.

If steroid sprays and antihistamines fail, or if you have perennial symptoms, your doctor may recommend trying allergy shots (immunotherapy), a treatment aimed at desensitizing your body's immune reaction to a particular allergen. In immunotherapy, increasing concentrations of the allergen are injected under your skin either weekly or biweekly. If immunotherapy is effective, allergy symptoms usually subside within six months to a year. Treatment often is continued for three to five years.

When to call a professional

Call your doctor if you think you might have hay fever and the symptoms interfere with your normal everyday activities or make you feel generally miserable, or if you have hay fever and your symptoms are not controlled by your current medications.

Prognosis

In most cases, hay fever can be managed successfully by minimizing exposure to the allergens and treating with one or more medications. Without medical treatment, most people with hay fever find that their symptoms gradually diminish as they grow older.

Additional info

American Academy of Allergy, Asthma & Immunology (AAAAI)
https://www.aaaai.org/