What is rhinitis?
Rhinitis is inflammation of the nose. It may, or may not, be caused by an allergy. Hay fever, the most common of the allergic diseases, is also known as seasonal allergic rhinitis. People with hay fever generally have symptoms throughout the pollen season (spring, summer, autumn), the exact period depending on the type of pollen (tree, grass, weed) that triggers the symptoms. Then there is perennial allergic rhinitis, where symptoms are present year round, irrespective of season, because the allergen is something other than pollen, like house dust mite or pet dander. However, some people have rhinitis year round, but find their symptoms are worse during the pollen season. Also, in some countries the pollen season is very long. So you may hear the term persistent rhinitis or intermittent rhinitis used to describe such cases.
Types of non-allergic rhinitis include triad and NARES. The name triad comes from the presence of three distinct symptoms: asthma, nasal polyps, and perennial rhinitis. Although triad does involve the immune system, it is not considered to be a classic allergy. Triad is strongly associated with a sensitivity to aspirin and related drugs. NARES stands for Non-Allergic Rhinitis with Eosinophilia and is marked by the presence of immune cells called eosinophils in the nose, where they cause severe inflammation. Then there is vasomotor rhinitis, whose exact cause is unknown. Triggers (not allergens) like spicy food, alcohol, stress, and air pollution can produce symptoms in vasomotor rhinitis. The presence of nasal polyps may also contribute to non-allergic rhinitis.
What are the symptoms of rhinitis?
They are similar to those of hay fever, namely:
- Red, watering eyes
- Sneezing
- Streaming nose
- Blocked nose/nasal congestion
- Itching of the nose, mouth, throat, eyes
- Dry throat
- Earache
- Loss of sense of smell.
Rhinitis may also be complicated by sinusitis, an inflammation of the sinuses, which are hollow cavities in the skull. Fluid from the sinuses normally drains into the nasal cavity but if this area is congested, then mucus will build up in the sinuses and this may become inflamed and infected. Another complication of perennial allergic rhinitis is post-nasal drip where mucus runs down the back of the nose, and then into the throat and the airways, producing a persistent phlegm cough.
What causes rhinitis?
Allergic rhinitis is caused by exposure to an airborne allergen. Common allergens include:
- House dust mite droppings
- Particles from insects such as midges, mosquitoes, cockroaches, carpet beetles, house flies
- Mould spores, indoors and outdoors
- Pet dander, especially from dogs, cats and horses
- Workplace allergens, such as flour, wood dust and chemicals.
Sometimes a food allergen can cause rhinitis. Yeast is probably the most common food allergen to produce nasal symptoms.
How common is rhinitis?
Allergic rhinitis (either seasonal or perennial) is common, affecting around 20% of the UK population. Around 50% of perennial rhinitis is thought to have an allergic cause.
What causes the symptoms of rhinitis?
What causes the symptoms of rhinitis?
The nose is a remarkable organ. It acts both as a heat exchanger and a filter. The nose is also well supplied with blood vessels (which is why a nose bleed produces so much blood). Cold air entering the nose flows past the turbinates, which are small bony projections on the breathing passages covered by mucous membrane. Particles and bacteria are trapped by the membranes, while the air is warmed by being drawn across the network of blood vessels that lies beneath the membranes.
In vasomotor rhinitis, the blood vessels may swell in response to small changes in environmental conditions, including irritants, which leads to congestion. Tiny abnormalities in the anatomy of the nose – in the turbinates, or the septum, which divides the nostrils, may contribute to this, In allergic rhinitis, blood flow is increased, the mucous membranes swell and there is increased mucus production, all occurring in response to histamine production on exposure to the allergen. The result is nasal congestion, nasal blockage, and a runny nose.
How is rhinitis diagnosed?
A simple account of your symptoms and their seasonality may be all that is required to diagnose rhinitis. If confirmation and/or identification of an allergic cause is needed, then a skin prick test can be used. A tiny drop of allergen extract is placed on the skin (either the arm or the back). If you are allergic to this substance, a small red weal will appear, usually within 15 minutes. Referral to a specialist is rarely necessary in simple cases of rhinitis, but should be done if you don’t respond to treatment (see below) or if there is doubt over the diagnosis.
Can rhinitis be confused with other conditions?
Nasal polyps and vasomotor rhinitis lead to similar symptoms to allergic rhinitis. It may be important to distinguish between an allergic and non-allergic cause for your nasal symptoms, as this will affect treatment.
Facial pain is not usual in allergic rhinitis and a referral to an Ear Nose and Throat Specialist should be made for further investigation.
What is the outlook in rhinitis?
Post-nasal drip can lead to a chronic cough, which is a symptom that always needs investigating. A cough that does not clear up within three weeks can indicate lung cancer. This is not to say there is any link between rhinitis and lung cancer – there isn't. But if you have a chronic cough, do not assume it is your rhinitis and ignore it. It may have a different cause.
Research has also suggested that about 40% of people with allergic rhinitis go on to develop asthma.
How can I prevent rhinitis?
Allergic rhinitis can be prevented by avoiding exposure to allergic triggers. Here are some pointers:
House dust mite
- Minimize allergen ‘reservoirs’ like carpets, sofas and curtains.
- Keep your home dry, which reduces mould as well as HDM.
- Invest in mite-proof covers for bedding.
Pet dander
- Confine your pet to one room in the house, or keep it outside.
- Wash the pet regularly with special shampoo and always wash your own hands after touching it.
- Pet dander gets airborne but also settles on carpets and soft furnishings. Keep the house ventilated and also vacuum regularly to suck up the allergen, using a vacuum with a HEPA filter to trap the particles.
Mould spores
- Keep your home dry by dealing with any cracks, leaks, or rising damp, and remove any visible patches of mould.
- When you are cooking, close the kitchen door and open a window. Do the same in the bathroom after taking a bath or shower. Don't have a carpet in the bathroom.
- Dry clothes outside wherever possible.
A HEPA air purifier may help reduce the allergen burden by improving the quality of your indoor air. The filter traps allergen particles with very high efficiency.
What medical treatments are there for rhinitis?
If your symptoms are mild, use a long-acting non-sedating antihistamine such as:
- Claritin (loratadine)
- NeoClaritin (desloratadine)
- Zyrtec (cetirizine)
- Xyzal (levocetirizine)
- Allegra (fexofenadine)
These are available over-the-counter (ask the pharmacist if you have questions about any of these medications). The older antihistamines like chlorpheniramine (Piriton) and hydroxyzine (Atarax) have a significant sedating effect and should not be used if you are driving, operating machinery, or studying. These older drugs also interact with alcohol so having even a small amount to drink may significantly affect performance. If rhinitis mainly affects your eyes, antihistamine eye drops, such as Otrivine (antazoline) (also available over the counter) may help
A nasal decongestant (drops or a spray) may also be helpful, in addition to your antihistamine, to clear a blocked nose. Some of these are corticosteroids, which act by reducing inflammation. These include Beconase (beclomethasone) and Flixonase (fluticasone). Meanwhile, Otrivine/Sudafed (xylometazoline) is a non-corticosteroid nasal decongestant. All of these can be bought without prescription. But only use a decongestant for as short a time as possible, because the nose tends to develop 'rebound' vascular congestion and will stop responding to the medication.
If antihistamines and nasal steroids do not do the job, then there is also Singulair (montelukast) which is a prescription medicine used for asthma and allergies. An antibody drug called Xolair (omalizumab) which targets the IgE antibody produced by the allergen has also been introduced recently. This approach gets to the root cause of allergic rhinitis, because IgE activates mast cells, making them produce histamine which triggers the allergic symptoms.
In general, antihistamines and topical nasal steroids do give some relief in perennial allergic rhinitis but tend to be less effective than in seasonal allergic rhinitis/hay fever. These drugs may also be effective in non-allergic rhinitis, where Singulair and related drugs may also be tried with some success.
Can rhinitis be cured?
Immunotherapy (also known as densensitisation or allergy shots) offers a way of overcoming allergic rhinitis for good. In the desensitisation approach, the system is ‘flooded’ with a known allergen so that the body will eventually learn to ‘ignore’ it. Patients for immunotherapy need to be carefully selected, and treated in a specialist centre. The procedure now involves only four injections and has been shown to give lasting benefit. There is also a home version known as sublingual immunotherapy, in which the patient places medication under the tongue (currently only available for grass pollen allergy). People with allergic rhinitis are more likely to have asthma, which fits in with the ‘united airway’ concepts which many allergy experts have noted. The significance of treating your allergic rhinitis for long-term results with immunotherapy is that it may prevent asthma in the future.
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