Children Allergy FAQs

What causes food allergies to specific foods has been researched for many years. When somebody has a reaction to food, that individual's immune system sees that particular food product – for example peanut – and thinks that it is something harmful for the body.

This is because people with food allergies have been exposed to that food in a way that made the immune system think that this was something harmful rather than something innocuous that wouldn't cause any problem.

When the individual then has contact with that food – say peanut – by either by eating it, some goes into their eye or if it's rubbed onto some broken skin, they could get an allergic reaction. This is because their immune system has already recognised that this is something that is foreign and needs to be dealt with.

Allergies, like most chronic conditions, are caused by a combination of genetic and environmental factors. More recently there has been a breakthrough in understanding that if a child has an inflamed disrupted skin barrier in the first year of life, and they are potentially exposed to allergenic foods through the skin, this causes the immune system to pick up on that food as something that is harmful to the body.

Going back to our previous example of peanut, the child then develops an allergic response to peanut and the next time the child is exposed to peanut the body starts to have an allergic response.

A top tip for those suffering from food allergies would be to get a proper allergy diagnosis so that they know exactly what it is that they are allergic to. For example, somebody could have a reaction to scrambled egg, and think that they're allergic to the egg, but it could be the milk that was used to prepare the scrambled egg. So, it's very important to get some proper allergy testing which can be done by skin test or a blood test using a specific IgE testing.

Once you have a formal allergy diagnosis, then you need to have a good understanding of the types of allergic reactions you might have. You could get an immediate allergy reaction which would cause hives and swelling and potentially anaphylaxis. Or it could be a delayed allergy reaction, in which case it would cause allergy symptoms later, a few hours after eating the food, and that could be skin rashes or eczema or gut issues.

You need to know how to identify the types of reactions that you're going to have and how to manage them. If you are experiencing a food allergic reaction, the first thing would be to stop eating the food that's causing the issue. You need to know how to manage the food allergy, including having a proper emergency plan, particularly for those with immediate food allergies that will need the right medication.

Then you need to ensure that you know how to avoid that food once you know what you are allergic to, such as by reading food labels properly. Telling people that you have an allergy is a good idea, so that they don't give it to you inadvertently.

It's also important to make sure that if you have a food allergy – for example to cow’s milk – and you avoid cow's milk in your diet, and that you make sure your diet has enough in the way of calcium, vitamin D and iodine. This is because you may lack those nutrients if you're not having cow's milk, so it's important to look into that to make sure that nutritionally your diet is complete. This is even more important when managing food allergies for children who are still growing and in breastfeeding mothers who have increased calcium requirements.

Whether the body can be trained in getting rid of food allergies is something that has been intensely researched in the last five to ten years. We know that with immunotherapy for inhalant allergens– for example for pollen allergies and house dust mite allergy – can have injections, take tablets or sprays under the tongue, which can help to retrain the immune system to be less allergic to those inhalant allergies.

When it comes to foods, in terms of certain foods that are naturally outgrown – for example most children outgrow their egg and milk allergy – there are things that can be done to help that individual outgrow their milk and egg allergy more quickly. This can be done by introducing baked forms of that food into the diet. Please that this does need to be done under medical supervision, rather than just at home.

There are certain food allergies that are more persistent, meaning that once a child has that allergy, usually they remain allergic for the rest of their lives. Examples include that only 20% of children outgrow their peanut allergy and only 10% of children outgrow tree nut allergies such as cashew and walnut allergy.

The question whether immunotherapy (also known as desensitisation) actually ‘gets rid’ of food allergy is really important because a lot of the media has been portraying this food allergy treatment as a cure. What the studies have shown is that it does not cure the food allergy but it does reduce the risk of accidental reactions to the food and reduces severity of allergic reaction if a reaction does occur.

The person doing the food allergy desensitisation or oral immunotherapy program needs to continue taking that food every day for the rest of their lives. This means that it's not something that would be defined as a ‘cure’. A cure would be that you no longer have to think about eating that food, you can just eat it whenever you want. Rather than a cure, we say it will make that individual ‘bite proof’. An example would be if they are peanut allergic and had some peanut by mistake in a restaurant, they would be much less likely to have an allergic reaction. Also if they were to have an allergic reaction, studies have shown that it is much more likely to be a milder allergic reaction than if they were not taking this treatment.

When it comes to food allergy reactions, you have two types of food allergy – immediate allergy reaction and delayed allergy reaction. Immediate food allergy causes hives and swelling, itchy, runny nose, vomiting, and in the most severe cases could lead to problems with the airway, breathing or consciousness.

For immediate food allergies symptoms – for example a skin rash hives, or swelling – then using a non-sedating antihistamine such as cetirizine is a good treatment. These can be bought over the counter for children over the age of two years, because it is licensed from that age. However, for children under the age of two, this would need to be prescribed.

In terms of more severe allergic symptoms such as problems with airway, breathing, or circulation, this is something that needs to be treated with adrenaline. This is also known as an anaphylactic reaction (a life-threatening allergic reaction). Adrenaline auto injectors are not available over the counter so they do need to be prescribed. This emergency medication is the gold standard treatment for anaphylaxis and if it is used you must always call 999 to get emergency services and say the word ‘anaphylaxis’.

It's so important when managing food allergies for you or your child, that you see somebody who is able to diagnose the allergy and any related allergies properly, and give you a personalised emergency plan to help you to recognise allergic symptoms and know how to manage them. Read more about how we can help with food allergy management.

When it comes to delayed allergies, the symptoms may be an eczema flare or maybe some gastrointestinal issues. For an eczema flare, many good moisturisers are available over the counter and the National Eczema Society has some great information about this. If the skin becomes very red and inflamed there are some topical steroids that can be applied. Some of these are available over the counter, and some need to be prescribed.

When it comes to the gut, and symptoms associated with the gut, it's very much about removing the offending food from the diet to see if that improves the symptoms. Sometimes some people can use a non-sedating antihistamine, like cetirizine which may help, but the main treatment would be to avoid the foods causing the symptoms.

Want to know more Allergic Rhinitis Facts? Read the full article on All you need to know about allergic rhinitis by the highly esteemed consultant paediatric allergist Dr Helen Brough.

Allergic rhinitis occurs as a result of the lining of the nose becoming inflamed. Typically, allergic rhinitis arises from inhaling seasonal allergens such as grass and pollen. It can also be triggered by perennial irritants like house dust mites and pet dander.

In addition to allergic inflammation of the nose, it can also cause lots of other symptoms, such as allergic rhinoconjunctivitis, which can also lead to inflammation of the lining of the eyes. Allergic rhinitis may impact the inner ear, leading to itchiness in the throat and tongue, and congestion in the nose.

Additionally, it may cause a mild cough. Individuals with asthma often experience an allergic cough due to allergic rhinitis known as allergy asthma. In some cases, it can be an extremely serious medical condition. Fortunately, there are a variety of different ways the condition can be treated.

The management of allergic rhinitis involves three aspects:

• Firstly, allergen avoidance is crucial, and patients can do so by identifying and avoiding their specific allergens.
• Secondly, symptomatic treatment is recommended, typically involving a non-sedating antihistamine nasal spray. Additionally, there are highly effective antihistamine-containing eye drops available for treating eye-related symptoms. Nasal steroid sprays are considered the gold treatment choice for symptomatic relief of allergic rhinitis as they can address itching, runny nose, and nasal congestion.
• The last aspect of treating allergic rhinitis is immunotherapy, which involves taking drops or tablets under the tongue to modify the immune system's response to specific allergens. This can help produce tolerant antibodies that reduce the severity of allergic reactions.

Grass pollen is the predominant trigger of seasonal allergic rhinitis in the UK, resulting in hay fever symptoms such as itching, sneezing, congestion, and frequent eye and nose rubbing among patients. Typically, individuals experience this condition from May through August. If pollen counts are high on a given day, this allergic condition can become especially severe.

House dust mites are the second most frequent trigger of allergic rhinitis, and their presence can exacerbate symptoms during winter when they are more abundant indoors. This allergy often results in severe congestion, a persistent cold-like sensation, headaches, and may also cause dark circles under the eyes.

The key symptoms to be aware of include eyes that are swollen and red, throat clearing caused by mucus build-up, an itchy nose and ears, as well as a dry, irritated cough at the back of the throat.

Allergic rhinitis can have significant consequences, particularly when it affects a child’s quality of life at school, disturbs sleep, or interferes with outdoor activities due to severe symptoms. In some cases, the condition may also result in sinusitis.

Want to know more Allergic Rhinitis Facts? Read the full article on All you need to know about allergic rhinitis by the highly esteemed consultant paediatric allergist Dr Helen Brough.

In children, a persistent dry cough can stem from various factors, and one potential cause is allergic asthma. Allergic asthma is the predominant form of asthma in children, where it is primarily influenced by a specific type of cell called the eosinophil.

An asthma flare is commonly triggered by environmental allergens like house dust mites or grass pollen. Fortunately, this type of asthma typically responds well to standard asthma treatment options commonly prescribed for asthma. Options for treating asthma include:

• Inhaled steroids: They are effective in preventing exacerbations or asthma attacks.
• Reliever inhalers (often blue): These inhalers work by relaxing the muscles in the airways, providing relief from symptoms.

In contrast, adults may experience different types of asthma, which can be associated with factors such as obesity. Effective management of asthma is crucial to safeguard the health of children with asthma and, therefore, it is vital to have a comprehensive understanding of the condition's indicators.

Wheezing is the primary and most frequently observed symptom of asthma in children. It manifests as a distinct high-pitched, whistling sound whilst breathing out. Wheezing is typically noticeable when a child is exposed to sudden cold weather, engages in physical exercise, or experiences an asthma exacerbation.

Note that many parents mistake wheezing for a rattling sound originating from the back of the throat. However, this type of sound is more commonly associated with post-nasal drip resulting from allergic rhinitis.

In addition to wheezing, a persistent dry cough can indicate uncontrolled asthma. This cough tends to occur predominantly at night, although not exclusively. It is crucial to approach the investigation of a chronic cough systematically, considering the various potential causes.

Different types of coughs have distinct characteristics, and their timing is also a crucial factor. For instance, habit coughs never occur at night when the child is asleep whereas asthmatic coughs do, underscoring the significance of both the timing and specific characteristics of the cough in determining its cause.

During an asthma attack in children, symptoms can extend beyond coughing and wheezing to include difficulty breathing. This is characterised by an increased effort in breathing, potentially leading to tugging in or the ribs or neck area, difficulty speaking, eating or walking.

To effectively manage such situations, it is crucial for the child to have a personalised asthma action plan in place. This plan equips the family with the necessary knowledge and instructions to address an asthma attack promptly and appropriately and how to get help.

Asthma is typically diagnosed in children aged five and older due to their developed motor skills, which allow for more advanced breathing tests. One commonly conducted test is spirometry, where the child inhales deeply and exhales forcefully to measure the volume of air expelled from their lungs.

As asthma involves airway obstruction, the inability to exhale rapidly suggests the presence of the condition. If obstruction is detected, a Salbutamol inhaler is administered to determine if the obstruction can be reversed through this treatment.

In addition to spirometry lung function testing, there are other diagnostic tests available for asthma. One such test is fractional exhaled nitric oxide (FeNO), which examines allergic inflammation in the lungs. These diagnostic tools aid in confirming and understanding the nature of asthma in children.

While tests like spirometry and exhaled nitric oxide are integral components of diagnosing asthma in children aged five and above, obtaining a comprehensive medical history and family history is equally crucial. Medical history assessment can begin from an early age, enabling an asthma diagnosis at any point.

When evaluating a child's history of asthma-like symptoms, it is vital to determine the onset of symptoms. Symptoms present from birth may suggest a structural issue, while symptoms that develop later may have different underlying causes.

Furthermore, the diagnostic process involves ruling out other potential conditions. For instance, a thorough examination aims to exclude chest infections or post-nasal drip caused by house dust mite allergies, which can result in a productive cough. By considering the medical history and eliminating alternative explanations, healthcare professionals can effectively diagnose asthma in children.

Recurrent viral infections often lead to a condition known as viral-induced wheeze in children. In such cases, the child experiences wheezing or coughing solely during episodes of cold but does not exhibit any asthma symptoms between these colds.

By considering the clinical history and conducting a thorough examination, we can determine the likelihood of asthma. If asthma is suspected, we may initiate a trial of inhaled steroids to assess if they alleviate or eliminate asthma symptoms.

Additionally, if the child is over five years old, we can employ a monitoring strategy called peak flows. This involves the child exhaling three times in the morning and evening to measure the speed at which they can exhale within one second. These peak flow measurements serve as a valuable tool for self monitoring asthma symptoms and can be integrated into a child's asthma action plan to effectively manage and control their asthma. We continue to review and observe the effects of the prescribed medication to ensure the best management approach for the child's asthma symptoms.

Even during the diagnostic phase, it is crucial to provide comprehensive inhaler device training to the child. Alongside this, a prescription for Salbutamol or another reliever inhaler should be given to the child, ensuring they are prepared in the event of an asthma exacerbation. This proactive approach helps to ensure the child's safety and prompt management of asthma symptoms, even while undergoing the diagnostic process.

In children, asthma frequently resolves, especially with the onset of puberty. This resolution is often attributed to the interplay between hormones and allergic asthma. Similarly, during pregnancy, asthma symptoms may improve or worsen. While some children may experience a temporary relief from asthma symptoms during puberty, there is a possibility of symptoms returning in adulthood.

Nevertheless, it is crucial to effectively manage asthma through proper assessment and treatment, rather than relying on the hope for spontaneous resolution. It is essential to recognise that asthma can be a potentially life-threatening condition. Therefore, proactive management and appropriate measures are imperative to ensure the well-being and safety of your child’s health.

Want to know more about symptoms and diagnosing asthma in children? Read the full article on Asthma in children: Symptoms and diagnosis by the highly esteemed consultant paediatric allergist Dr Helen Brough. More information can be found on our Asthma Treatment London page.