Some people have allergy symptoms such as sneezing and a stuffy nose all year round. This might be caused by an allergy against things like animal fur, mold or dust mites.
If someone has an allergic reaction to substances such as pollen or animal fur that affects their upper respiratory tract (upper airways), it is called “allergic rhinitis."
Symptoms
People who have allergic rhinitis sneeze a lot and have a runny or stuffy nose. If their symptoms are more severe, they might also feel weak and tired. Sometimes people have watery and itchy eyes, and their eyelids become swollen too. The medical term for this is allergic rhinoconjunctivitis (allergic rhinitis combined with conjunctivitis). Further possible hay fever symptoms include itching, and asthma symptoms like coughing, wheezing and shortness of breath.
Causes and risk factors
Allergy symptoms arise when your body overreacts to particular substances that are usually harmless, such as pollen. These substances (allergens) trigger a chain reaction in the immune system. First of all, antibodies against the allergen are made. The antibodies then attach themselves to certain cells. If they come into contact with the allergen again, these cells are then able to “respond”: they release chemical substances, including a substance known as histamine. These substances then lead to allergic reactions such as sneezing, coughing and skin rashes.
Allergic rhinitis can be triggered by things like dust mites, animal fur, pollen and mold.
Sometimes a higher risk of allergies runs in families. Environmental factors such as air pollution and cigarette smoke can make allergies more likely too.
Other things that are believed to contribute to the higher prevalence of allergies nowadays include higher hygiene standards and the fact that some infections have become less common in childhood. This means that our immune systems are often not as “well trained” as they might have been in the past.
Frequency and outlook
Allergic rhinitis affects about 1 out of 4 people in industrialized countries like Germany. It usually first arises before the age of 20.
Allergic rhinitis might develop into allergic asthma after several years. Sometimes people who are allergic to pollen, for instance, become allergic to certain foods too after a while. This is known as cross-reactivity.
Effects
Severe symptoms can lead to other medical conditions such as sinusitis (inflammation of the sinuses). Allergic rhinitis makes mucous membranes overly sensitive in a lot of people. As a result, non-allergic irritants like dry air in heated rooms and cigarette smoke cause worse nasal symptoms than they do in other people.
Diagnosis
If you see a doctor, he or she will first ask you about your symptoms, everyday life, and medical history. The doctor can then do a skin prick test to find out whether you are allergic to particular substances. This involves placing small drops of various allergens on the skin of your forearm, with enough space between them, and then pricking the surface of your skin where the allergens are, so the substances go into the skin. If your skin becomes red and swollen in a certain place, similar to a big mosquito bite, it is a sign that you are allergic to the substance that was put there.
You might also need a blood test or something known as a nasal provocation test. This is where the mucous membrane lining of the nose is exposed to extracts of the potential allergen using a nasal spray or drops. If the lining of your nose becomes swollen, you sneeze and your nose starts running, you are likely to have allergic rhinitis.
Prevention
Women can somewhat lower the risk of their child developing an allergy by breastfeeding their child in the first few months after the birth, and - if they smoke – by quitting smoking before they become pregnant. But allergies cannot always be prevented.
The most effective way to prevent allergy symptoms is to avoid the substances that trigger the allergy. How well this works will mainly depend on the type of trigger. It is quite easy to avoid contact with things like animal fur or chemical substances. But it is almost impossible to avoid pollen. If you are allergic to dust mites, a combination of various changes in the bedroom might help.
These include wiping the floor with a damp cloth, using mite-proof mattress and bed covers, removing “dust traps” such as upholstered furniture and curtains, and regularly washing your bedding at temperatures above 55°C (130°F). But it is not possible to avoid contact with dust mites completely.
Treatment
Medications
Although medications for the treatment of allergic rhinitis can have side effects, they are usually well tolerated. Various medications can reduce the symptoms. The most suitable one will depend on a person’s individual situation and can be discussed with a doctor.
Factors that influence the choice of medication include the severity and type of allergic rhinitis (seasonal or year-round), as well as personal preferences and experiences. For instance, some people would prefer to take tablets rather than use a nasal spray. Others might feel tired when they use a certain medication, and decide to try a different one instead. Age and other things like medical conditions or pregnancy can play a role too.
Various medications are available for the treatment of the symptoms:
- Antihistamines
- Steroids (corticosteroids)
- Chromones
- Leukotriene receptor antagonists
- Decongestant nasal drops and sprays
Antihistamines
If something triggers an allergic reaction in your body, your immune system launches a response, releasing histamine. Histamine causes allergy symptoms like sneezing, watery eyes and skin rashes. Antihistamines block the action of histamine. When treating allergic rhinitis, antihistamines can be used in the form of tablets or nasal sprays. Tablets start working within a few hours, and nasal sprays start working within15 minutes.Research has shown that tablets and nasal sprays can both provide effective relief. They are usually well tolerated. The most common side effects of tablets are tiredness and headaches. Newer generation antihistamines work in a similar way to older ones, but they have fewer side effects. For instance, they are a lot less likely to make you feel tired, which can make a big difference if you have to drive a car or do other activities that require concentration. For this reason, older antihistamines (“first-generation antihistamines”) are generally no longer recommended. Nasal sprays can leave a bitter taste in your mouth.
Corticosteroids
Corticosteroids are steroid drugs that contain the anti-inflammatory hormone cortisone. Corticosteroid nasal sprays reduce swelling in the mucous membranes and relieve symptoms like a runny or blocked nose. They can be used over longer periods of time, but it is then advisable to see a doctor regularly for check-ups. Although they do not have an immediate effect, people usually notice an effect within twelve hours. The full effect is reached after a few days. They might cause mild side effects such as nose bleeds, headaches or altered taste.
Leukotriene receptor antagonists
These medications block the action of leukotrienes – chemical messengers that play an important role in the inflammatory response that happens in the airways. In Germany they are licensed in the form of tablets for the treatment of asthma. As well as relieving asthma symptoms, they can also relieve the symptoms of hay fever. So doctors can also prescribe leukotriene receptor antagonists for people above the age of 15 who have both asthma and seasonal allergic rhinitis. Possible side effects include respiratory tract infections (infections of the airways) and headaches.
Chromones (mast cell stabilizers)
Mast cell stabilizers prevent histamine from being released by certain cells in the body known as mast cells. This reduces allergic and inflammatory responses in the body. They are used in the form of nasal sprays, and are usually used to prevent symptoms, but they can also relieve symptoms. Possible side effects include irritation of the membranes lining the nose, and an unpleasant taste in your mouth.
Decongestant (anti-swelling) nose drops and nasal sprays
Decongestant nose drops and nasal sprays reduce swelling in the mucous membranes lining the nose and the sinuses, making it easier to breathe through your nose. They are not suitable for the long-term treatment of allergic rhinitis, though. Although they open your nasal passages and make it easier to breathe at first, your nose might “get used to them” after a short while, and then they have the opposite effect: The membranes become swollen again and it is difficult to breathe through your nose. These medications can also cause side effects like nosebleeds. So it is recommended that these medications not be used for longer than 5 to 7 days.
Do some medications work better than others?
There are no big differences between the medications – at least not in the treatment of seasonal hay fever. Corticosteroid nasal sprays are often recommended as the treatment of first choice. They are just as well tolerated as other medications, and they might be somewhat more effective, for instance than antihistamines. But studies suggest that the differences between the effects of these two types of medications are not very big either.
If the symptoms do not improve enough, a different medication can be tried out instead, or two medications can be combined (e.g. a corticosteroid nasal spray and antihistamine tablets).
Washing the nose
There are also non-drug alternatives such as saline (salt water) nasal sprays and nasal washes (nasal irrigation). Research has shown that saline (salt water) nasal sprays and nasal irrigation can help relieve the symptoms. They can be used on a daily basis. If someone has more severe symptoms, these products are usually not effective enough on their own, but they can be used in addition to other medications. People might get by with less medication as a result. Saline nasal products are available in drugstores, pharmacies and supermarkets.
avoiding exposure to allergens
The most effective way to prevent the symptoms is by avoiding exposure to allergens (allergy triggers) in the first place. Whereas some allergens are easy to avoid, others are very difficult or impossible to avoid. Trying to prevent contact with allergens, such as dust mites in your home, is not always worth the amount of effort involved.
If the allergy symptoms are mild, saline (salt water) solutions might also help relieve symptoms in the nasal area.
Avoiding mold and animal fur is easier than avoiding pollen. It is almost impossible to protect yourself from pollen, unless you travel to areas of the world where there is no pollen in the air. When the pollen count is high, people who have a pollen allergy (hay fever) can prevent symptoms by doing things like closing their car windows when driving, and washing their hair before going to sleep. Local weather reports often provide information about pollen forecasts and current pollen counts.
Some people are allergic to mold (fungal spores). It is then important for them to prevent mold from growing in their home, for example by opening windows regularly and heating enough. Damp walls need to be dealt with, and already existing mold should be removed.
If you are allergic to dust mites, taking certain precautions in your home can help prevent allergic rhinitis. Dust mites are mainly found in mattresses and bed covers, so a combination of various changes in the bedroom might help. These include wiping the floor with a damp cloth, using mite-proof mattress and bed covers, regularly washing your bedding at temperatures above 55°C (130°F), and removing “dust traps” such as upholstered furniture and curtains. Doing just one of these things alone does not make much of a difference, though.
Dust mite sprays containing acaricides (pesticides against mites and ticks) could also help relieve symptoms. They are sometimes sprayed under mattress covers. Special dust mite air filters are available too, but it is not clear how effective they are.
Acupuncture or acupressure
Some doctors and many alternative practitioners offer acupuncture or acupressure for the relief of allergic rhinitis symptoms. A number of studies have looked into whether acupuncture or ear acupressure can help relieve the symptoms. Unfortunately they did not come to any clear conclusions – but real improvements cannot be expected from these treatments.
Desensitization
A treatment known as allergen-specific immunotherapy (“desensitization”) can help reduce sensitivity to allergens in the long term. Like with vaccines, this treatment approach involves exposing people to small amounts of the allergen. Here it is done at regular intervals by either injecting the allergen into your skin or dissolving a tablet under your tongue. Allergen-specific immunotherapy takes about three years to complete.
People who have hay fever or a dust mite allergy sneeze a lot, and have a runny or stuffy nose. Many of those who have very severe and bothersome symptoms try out allergen-specific immunotherapy. This treatment aims to make the immune system “get used to” the substances triggering the allergy, so that it no longer reacts as strongly to them.
The goal of allergen-specific immunotherapy is to reduce allergy symptoms in the medium to long term. It has to be repeated regularly and takes quite a long time to start working. In the past this treatment was commonly called "desensitization" or "hyposensitization." These terms describe what it aims to do: make the immune system less sensitive. In people who are allergic to something, their body is oversensitive or hypersensitive to an allergen (the substance that causes their allergic reaction). Their body produces antibodies to fight the allergen, even though the allergen is harmless. These antibodies are part of a chain reaction that leads to allergy symptoms. In allergen-specific immunotherapy, people are given allergen extracts to try to train their body to react differently: It is a bit like being “vaccinated” against your own allergy.
Allergen-specific immunotherapy (SIT) cannot be used for every allergy. It is called "specific" because the allergen extract has to be tailored to the individual person's allergic response. There are still no suitable SIT extracts for some substances that cause allergies. But there are extracts for many of the common allergens found in the air, for mold, for animal allergens, and for some toxic substances (like the poison in bee stings).
In specific immunotherapy, the person is repeatedly given a very small amount of "their" allergen or allergens. First of all, a test is done to check whether the person really is allergic to a certain substance. To allow their body to get used to the allergen, only a very small amount of the substance is used at first. The dose is increased from session to session until the person reaches their personal maximum dose, which is then given at regular intervals.
If they have severe side effects, the dose is reduced again. It is then also a good idea to rule out other possible causes too. Should no other causes of these symptoms be found and treated, the dose might be increased again. It should be as high as possible without causing too much of an allergic reaction. So both the person getting the treatment and the doctor need to watch very carefully for reactions.
People who have allergen-specific immunotherapy have to go to the doctor regularly. Sometimes there is already a noticeable improvement in symptoms within the first year. But it typically takes at least two to three years before the treatment reaches its full effect. It is also not unusual for immunotherapy to take five years, particularly when treating allergies against the poison in bee or wasp stings. The allergen is given every week or two at first. Later on it is given less often, usually once a month. Generally speaking, only one allergen extract is used at a time. Several extracts can also be mixed and used together, but there is very little research on treatment with these kinds of mixtures. In Germany, the costs of allergen-specific immunotherapy are covered by the statutory health insurances.
The allergen extracts can be given to people through injections. The medical term for this approach is "subcutaneous immunotherapy” (SCIT) because the extracts are injected just under the skin (subcutaneously). The injections are sometimes referred to as “allergy shots.” There is also another option called “sublingual immunotherapy” (SLIT). This involves giving people extracts in the form of drops, tablets or sprays which are kept under the tongue (sublingual) for a while and then swallowed. These are sometimes called "allergy drops."
Both kinds of allergen-specific immunotherapy (injections and under the tongue) are effective treatments. Many studies have shown that they can relieve the symptoms of allergic rhinitis and reduce the need for medication.
But there is no guarantee that this treatment will work. In some people it does not provide any relief from sneezing, swollen mucous membranes, and itchy and watery eyes. Sometimes the symptoms become worse again after the treatment. But allergen-specific immunotherapy has many important advantages over all other allergy treatments: in many people it can prevent the original allergy from developing into allergies against other substances too, or from developing into asthma. And it is the only treatment approach that directly targets the cause of the symptoms. So if allergen-specific immunotherapy is successful, less medication is needed, or no medication is needed at all anymore.
Research has shown that immunotherapy is effective in the treatment of hay fever and year-round (perennial) allergic rhinitis. In other words, it is suitable for people who are allergic to tree, weed and grass pollen, and it is also suitable for people who are allergic to dust mites. There is not as much good research on how well it works in people who are allergic to animal fur. Some studies suggest that it could also be effective in people who are allergic to cats, though.
There is good evidence that immunotherapy works well in adults and children. But not much is known about the benefits and risks of this treatment in pregnant women, older people and people who have severe asthma.
Mild and temporary side effects are very common with allergen-specific immunotherapy. This is to be expected when a person is given a substance that they are usually allergic to. The likelihood of side effects depends on things like
- how sensitive they are to the allergen,
- how high the dose is, and
- which drug is used.
About 10 to 60 out of 100 people develop a mild skin rash at the site of injection. When allergens are placed under the tongue, itching and swelling in the mouth are common. Up to 50 out of 100 people have allergic reactions such as sneezing, watery eyes or asthma symptoms at least once. Tiredness and headaches can occur too. Although these side effects are usually mild and temporary, sometimes they need to be treated.
The biggest concern is that allergen-specific immunotherapy will cause an extreme allergic response called "anaphylactic shock." This can lead to breathing difficulties, circulation problems and unconsciousness. In the worst case anaphylactic shock is a life-threatening condition, so it is a medical emergency and must be treated by a doctor immediately. Sometimes a drug called adrenaline is injected to quickly counteract the body's reaction.
Anaphylactic shock is very rare in people who are otherwise healthy. The risk of developing it can only be roughly estimated. In studies, fewer than 1 out of 1,000 people who were given “allergy shots” had a reaction that had to be treated with adrenaline. It is because of this small risk, though, that precautionary measures are taken: every time someone is given an allergen extract, they must stay in the doctor’s office for at least 30 minutes afterwards. Your doctor should also describe the symptoms of anaphylactic shock to you, and make sure your family is informed too. If you then start showing signs of this extreme reaction when you are no longer at the doctor’s, immediate medical help can be sought.
The risk of anaphylactic shock is much higher for some people. For instance, certain heart problems can increase the risk, and if you are taking beta-blockers it is harder to treat possible side effects. So people with cardiovascular (heart and blood vessel) disease can usually only have allergen-specific immunotherapy if beta-blockers are replaced with other medications. People with severe asthma can have immunotherapy if their asthma is well controlled and stable. If you have had an allergic reaction to an injection in the past, it is important to tell your doctor about it before starting allergen-specific immunotherapy.
It is not yet possible to say for sure whether one type of allergen-specific immunotherapy is better than the other. Several studies have compared the two treatments with each other. They suggest that injections could relieve the symptoms somewhat more effectively than medication placed under the tongue in the form of tablets or drops. But because both treatment approaches at least have a similar effect, the treatment decision can be based on personal preferences.
Surgery
Sometimes surgery is carried out to make it easier for people to breathe through their nose again. This might be done if someone has very severe symptoms, and has tried out medication and other interventions, but still cannot breathe well enough through their nose. Surgery does not make the allergy go away, though.
Source: Institute for Quality and Efficiency in Health Care