What Is Allergic Rhinitis?

Overview

Allergic rhinitis, commonly known as Hay fever, is the inflammation and swelling of the nasal mucous membranes following inhalation of an allergen.¹ It is not life-threatening in itself unless it is accompanied by asthma or a severe allergic reaction called anaphylaxis. However, allergic rhinitis can pose significant morbidity, affecting the quality of life and work performance as well as increasing health costs. This condition is the body's response to allergens (substances your body is allergic to) such as dust mites, animal danders, and molds as though they are harmful. Non-allergic causes are perfumes, cigarette or other smoke, chemicals, cold air, and strong odours. Hay fever is very common and affects approximately one in five persons in the UK.

Allergic rhinitis can be classified as either seasonal (intermittent or at specific seasons) or perennial (chronic or occurring throughout the year) with approximately 20% of cases being seasonal, 40% being perennial, and 40% having features of both. It can also be classified based on severity into mild, moderate, and severe.²

Allergic rhinitis doesn't just affect the nasal mucosa alone, it could present with other allergic forms like allergic conjunctivitis, chronic sinusitis, non-productive cough, and Eustachian tube dysfunction. Most persons trivialise their symptoms and do not seek medical attention. On the other hand, people with moderate to severe forms may not experience relief with just over-the-counter medications, hence the need to visit an allergic specialist. There are various modalities of treatment for allergic rhinitis which will be discussed in this article.

Causes of allergic rhinitis

Allergic rhinitis begins with the inhalation of allergens. The tendency to develop allergic reactions has a genetic component. Upon exposure to a certain allergen that your body senses as "harmful", several reactions take place with the end product being the release of certain body chemicals like histamine, kinin, and heparin which are responsible for the symptoms seen in allergic rhinitis and other allergic conditions.

These allergens include:

• Tree/ grass pollen
• Dust mites
• Animal danders (old flakes of skin from animals)
• Animal saliva (cat)
• Molds
• Tobacco smoke
• Cockroach droppings

Other factors which will usually cause more non-allergic rhinitis:

• Cigarette smoke
• Chemicals
• Cold temperature
• Humidity
• Wind
• Air pollution

• Hairspray
• Perfumes/ colognes
• Wood smoke
• Fumes

Signs and symptoms

Signs and symptoms of allergic rhinitis include:²

• Sneezing
• Itching of nose, eyes, ears, palate, throat
• Runny nose
• Postnasal drip
• Congestion (blocked nose)
• Anosmia (inability to smell)
• Headache
• Earache
• Tearing
• Red eyes
• Eye swelling
• Fatigue/ drowsiness
• Bad breath
• Malaise
• Allergic shiners (Dark circles around the eyes)

Pediatric allergic rhinitis could present in the following ways:

• Recurrent ear infections
• Snoring
• Poor performance at school
• Mouth breathing
• Poor growth

Allergic rhinitis can lead to significant impairment of quality of life and can also lead to various complications.

These compilations of allergic rhinitis include:

• Acute or chronic sinusitis
• Otitis media (Middle ear infection)
• Sleep disturbance or sleep apnea
• Dental problems (overbite): following excessive breathing through the mouth
• Palatal abnormalities
• Eustachian tube dysfunction
• Worsening asthmatic episodes

Allergic rhinitis is associated with certain comorbidities and it has been known to worsen them, leading to worsening morbidity and even death. Some of these conditions are:

• Asthma
• Atopic dermatitis (Eczema)
• Nasal polyps

You are more likely to have allergic rhinitis if a family member has eczema or asthma. They are all various spectrums of allergic manifestations. The symptoms improve with time but are unlikely to disappear completely.

Management and treatment for allergic rhinitis

Once you notice you have any of the symptoms suggesting allergic rhinitis, you should visit your doctor. Your doctor would ask you questions about your symptoms and possible symptoms in family members after which some investigations like skin prick testing to identify specific allergens will be done. This test involves the use of a drop of allergens within your environment on your forearm or back. The skin is pricked through the drop to introduce the allergen. A wheal or flare response (redness and swelling) within 15 to 20 minutes is a positive test (meaning you are allergic to the said substance). Other blood tests may be requested. Your doctor could also refer you to an allergist or immunologist for specialist care.

Other conditions that can mimic allergic rhinitis are:

• Vasomotor rhinitis
• Nasal polyposis
• Infectious rhinitis
• Cerebrospinal fluid leakage
• Drug-induced rhinitis (NSAIDs, nasal decongestants, ACE inhibitors)
• Rhinitis of pregnancy/ hormonally-induced rhinitis
• Chemical rhinitis

This is why you should visit your doctor once you have symptoms so that you can be managed appropriately.

For treatment, four strategies are recommended:

1. Avoiding triggers
2. Use of medications to reduce symptoms
3. Allergen immunotherapy (Allergic shots)
4. Surgical management

Avoiding triggers

Complying with methods to reduce contact with triggers will substantially improve symptoms.

These methods are:

• Close your windows and doors, especially during pollen seasons
• Use goggles and masks
• Reduce outdoor activities during high pollen counts
• Use air-conditioners as they are preferred to window fans which allow pollen in
• Drive with windows closed during pollen seasons
• If you have pets, you should bath them weekly and keep them off furniture and bedrooms
• To avoid dust mites, keep pillows and mattresses sealed in plastic covers
• Keep carpets off your bedroom
• Use humidifiers for a relative humidity of less than 50%

Use of medications to relieve symptoms

Pharmacological options include the following:

Anti-histamines

These drugs which are commonly prescribed as over-the-counter tablets relieve symptoms of itching, sneezing, and runny nose. They are the first-line drugs used in treating allergic rhinitis. They are highly effective when taken regularly at the height of symptoms or even before exposure to an allergen. Antihistamines are prescription drugs available as tablets and are also available as intranasal sprays. Examples are loratidine and cetirizine.

Intranasal corticosteroids

Intranasal steroids are first-line drugs for mild or moderate to severe allergic rhinitis. When used correctly and regularly, they reduce inflammation of the nasal mucosa. They also reduce eye symptoms associated with allergic rhinitis. Common side effects include nasal irritation and stinging. Examples are beclomethasone and fluticasone.

In some cases, both corticosteroids and antihistamine nasal sprays are combined for higher efficacy.

Leukotriene receptor antagonists (LTRAs)

These are not as effective as intranasal corticosteroids but are effective for removing nighttime and nasal symptoms, especially in the short-term treatment of allergic rhinitis. An example is Montelukast.

Nasal decongestants

They are useful for managing nasal congestion. Do not use them for more than 3 – 5 days to avoid rebound nasal congestion. Examples are phenylephrine and oxymetazoline.

Allergen Immunotherapy (Allergic shots)

This concept entails the gradual introduction of increasing quantities of an individual's specific allergens subcutaneously (just beneath the skin) until it gets to a quantity enough to induce immunologic tolerance to that allergen. It is very effective in treating allergic rhinitis, especially in those with the seasonal (intermittent) form. Allergic shots are given 3 – 4 weekly for 3 – 5 years after which you can have prolonged periods without having allergic rhinitis and a consideration by your doctor to stop the therapy.^2,3

Surgery

This option only applies to chronic sinusitis and nasal polyps that do not necessarily respond to medical treatment.

FAQs

How is allergic rhinitis diagnosed?

A person is said to have allergic rhinitis when they have symptoms like sneezing, runny nose, itchy nose or throat, and tearing. Such symptoms are most of the times seasonal, for instance, around pollen seasons, windy periods, and after exposure to dust or animals. Further confirmation is done by a skin-prick test to identify specific allergens especially those within the patient's environment. The allergist could also do some blood tests and get information about your family members with similar symptoms, environmental triggers, frequency, and severity of your symptoms.

How can I prevent allergic rhinitis?

Identifying triggers or irritants is the first step in trying to prevent allergic rhinitis. After this, you should avoid them as much as possible. Regarding outdoor irritants, you should close windows and doors, use a goggle and a nose mask, avoid spreading clothes outside, especially during pollen seasons, avoid window fans which bring in more pollen into the house and do not rub your eyes as this could aggravate your eye symptoms.

To prevent indoor exposure, avoid dust mites by using mite-proof covers for pillowcases, duvets, and mattresses. Keep humidity in your room low to less than 50% to avoid molds growing around the house. Keep your home well-ventilated. Clean the floors and working surfaces regularly.

Avoid pets if you can or else, wash your hands after touching them and bathe them regularly. Replace carpets with hardwood or tiles to reduce dust mites exposure.

Who is at risk of allergic rhinitis?

People who are genetically predisposed to allergies (atopic individuals) are more at risk.⁴ If you have a family member with allergic rhinitis, eczema, or asthma you are at risk of having not just allergic rhinitis but any of these allergic conditions. People with asthma are at a higher risk of developing allergic rhinitis than the normal population. The highest prevalence of allergic rhinitis is seen in children than in adults. In childhood, it is more common in boys than girls but in adulthood, there's just a slight difference in its occurrence between people assigned males and females at birth.⁴

How common is allergic rhinitis?

Allergic rhinitis is the commonest cause of rhinitis. It is extremely common and affects over 20% of the world's population. It occurs in people of all races and the onset is very common in childhood, adolescence, and early adult years.

When should I see a doctor?

You should see your doctor when your symptoms don't seem to be resolving despite attempting to avoid allergens or if you develop new symptoms. Also, seek medical care if you aren't sure what to do when you have symptoms of allergic rhinitis.

Summary

Allergic rhinitis is an extremely common disorder that can significantly impair an individual's quality of life. It is the body's reaction to certain allergens which the body sees as harmful. Certain substances are released and are responsible for the myriad of symptoms seen in allergic rhinitis. There is a genetic component to this condition and most patients have family members who have one or two allergic conditions like asthma, eczema, or allergic rhinitis. Allergic rhinitis can be seasonal or perennial. One of the most important steps in its treatment remains environmental modifications whereby the individual avoids allergens that trigger episodes of allergic rhinitis. Furthermore, drugs like antihistamines, intranasal corticosteroids, and allergen immunotherapy are prescribed based on the doctor's discretion in selected cases. A skin prick test can identify specific allergens and further confirm the diagnosis of allergic rhinitis. Prevention is by avoiding triggers and this is important as this can reduce symptoms significantly even before the use of medications.