Rhinitis, including hay fever, is the most common of all the allergic diseases. The typical symptoms such as blocked nose, watery eyes, & running nose may persist all year round (perennial rhinitis) or may be seasonal. Even though it’s often undiagnosed and its symptoms often perceived as harmless, the actual impact perennial rhinitis could have on a person’s overall quality of life is significant.
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 rhinitis 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 the season because the allergen is often something other than pollen, like house dust mite, pet dander or traffic pollution. However, some people have rhinitis year round but find their symptoms are worse during the pollen season. In some countries, the pollen season is very long. So you may hear the term persistent 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. 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 like spicy food, alcohol, stress, and air pollution can produce symptoms in vasomotor rhinitis.
Allergic rhinitis is common, affecting around 20% of the UK population. Around 50% of perennial rhinitis is thought to have an allergic cause.
They are similar to those of hay fever, namely:
Another symptom of perennial allergic rhinitis is post-nasal drip, where mucous runs down the back of the nose and then into the throat and the airways, producing a persistent phlegm cough.
Allergic rhinitis is caused by exposure to an airborne allergen. Common allergens include:
Sometimes a food allergen can cause rhinitis. Yeast is probably the most common food allergen to produce nasal symptoms.
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 nosebleed 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 lie 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/or a runny nose.
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 at either the arm or the back. If you are allergic to the substance, a small red weal will appear, usually within 15 minutes.
Nasal polyps and vasomotor rhinitis lead to similar symptoms of 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.
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. Furthermore, research has also suggested that about 40% of people with allergic rhinitis go on to develop asthma.
Allergic rhinitis can be prevented by avoiding exposure to allergic triggers. Here are some useful tips:
House dust mite:
If your symptoms are mild, use a long-acting non-sedating antihistamine such as:
These are available over-the-counter and you should always consult your pharmacist or GP before use. The older antihistamines 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 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. Most of these can be bought without a prescription. However, you should 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.
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 other drugs may also be tried with some success.
Immunotherapy offers a way of overcoming allergic rhinitis for good. In this desensitization 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, this is currently only available for grass pollen allergy. People with allergic rhinitis are more likely to have asthma. The significance of treating your allergic rhinitis for long-term results with immunotherapy is that it may prevent asthma in the future.
To find out more about the effects that rhinitis can have on your everyday life, click here.