Common Allergies: Causes, Treatments, and Remedies

An allergy is when your body overreacts to a substance or food. According to the NHS, one in four people is thought to be affected by an allergy in their lifetime, with children most affected.

The latest allergy data shows that 40% of children have been diagnosed with an allergy in the UK alone.

Most allergic reactions are mild and treatable with allergy medicine, but there is the possibility of anaphylaxis, a serious, life-threatening reaction.

Allergens are responsible for causing an allergic reaction. The more common ones include:

• Grass and tree pollen: allergy known as hay fever or allergic rhinitis
• Dust mites: waste and shed skin
• Food: particularly nuts, fruit, shellfish, eggs and cow’s milk
• Bites and stings from insects
• Medication: including painkillers and antibiotics
• Latex: used to produce gloves and condoms
• Dead skin cells or hair from animals
• Mould: release of small particles into the air that you can breathe in
• Household chemicals: including those in detergents and hair dyes

Most people who are allergic to these allergens will have a mild reaction.

Allergies are basically your immune system overreacting to something that’s normally harmless.

Your immune system is designed to protect you from real threats like bacteria, viruses, and parasites. It sometimes mistakenly uses the same mechanism for allergens that pose little threat.

It’s still not fully understood why this occurs. What we do know is that if a member of your family is reactive to allergens, you are likely to be too.

People with closely linked conditions like asthma and eczema are more prone to allergies because of the shared environmental and genetic factors.

The best way to manage allergies is to avoid the triggers that cause them. You can also relieve symptoms with allergy medications, and in some cases, retraining your immune system. Here are a few handy tips on managing allergies:

• Food allergies: read labels carefully, tell restaurants about your allergies, and carry an epinephrine auto-injector (like EpiPen) if it’s severe
• Pollen allergies: avoid outdoor activities on high pollen count days, keep doors and windows closed, and use antihistamine tablets.
• Dust mites and dead skin cells: regularly clean your environment and keep pets out of your bedroom
• Insect bites and stings: use a repellent and cover up your skin when outdoors
• Severe allergies:  always carry an auto-injectable device such as an EPI-PEN, which delivers the drug epinephrine in the case of a severe reaction.
• Retrain and strengthen immunity: boost your diet with fruits and vegetables, get adequate amounts of sleep, and maintain a moderate intensity workout routine.

Although these allergy management strategies can be effective, there are times when it may not be possible to avoid allergies.

In these cases, you can thankfully turn to allergy medications that offer rapid relief, including:

Antihistamines

Histamine is a chemical that the body releases when it detects something potentially harmful.

It triggers the widening of blood vessels and can cause swelling in the skin, which is a natural defence mechanism meant to protect the body.

Antihistamines help by blocking histamine’s effects on cells, reducing allergic symptoms. Some common examples of antihistamines include:

• Chlorphenamine (Piriton)
• Desloratidine 
• Fexofenadine (Telfast)
• Levocetirizine (Xyzal) 
• Loratadine (Clarityn) 

Decongestants

Decongestants provide quick relief from a stuffy nose by shrinking swollen nasal blood vessels, allowing air to flow more freely. They’re best used short-term to ease congestion. Some common decongestants are:

• Pseudoephedrine (Sudafed/Actifed)
• Phenylephrine
• Oxymetazoline (Vicks Soother nasal spray)

Steroid Medication

When allergies trigger inflammation, certain steroid-based treatments can help calm the body’s response and ease symptoms. Common options include:

• Fluticasone (Flixonase, Dymista, Avamys)
• Beclomethasone (Beconase) 
• Mometasone (Nasonex) 
• Budesonide (Benacort)

For people with severe, long-lasting allergies that don’t respond to standard treatments, allergy immunotherapy may be a suitable option.

This approach works by gradually introducing small, controlled amounts of the allergen to help the immune system become less sensitive over time.

Typically delivered through injections, sublingual drops, or tablets, the process can span several years and is mainly used to treat environmental allergies like pollen, dust mites, insect stings, or allergic asthma. Its effectiveness for food allergies remains uncertain, so it’s not generally recommended for that purpose.

If you’re experiencing symptoms that could be related to an allergy, it’s important to speak with your GP.

If the trigger is obvious, your doctor may recommend lifestyle changes or medications to help manage your symptoms. However, if the cause is unclear or your reactions seem more serious, you may be referred to a specialist clinic or hospital for allergy testing. Common tests for diagnosing allergies include:

• Blood Test: A sample is analysed for specific antibodies that the immune system produces in response to allergens.
• Skin Prick Test: A tiny amount of a suspected allergen is placed on your skin, usually the forearm, then lightly pricked with a small needle. If you’re allergic, a red, itchy bump typically appears within 15 minutes.
• Patch Test: Used to diagnose contact dermatitis (a type of eczema triggered by allergens touching the skin). A patch containing the suspected allergen is applied to the skin and monitored for a delayed reaction.
• Elimination Diet: This method helps identify food allergies by removing suspected foods from your diet for a period. If symptoms improve, the food is gradually reintroduced to check for a reaction.
• Challenge Test: Often used under medical supervision, this involves consuming small, increasing amounts of a potential food allergen to observe any response.

Important: Online allergy testing kits are generally considered unreliable and don’t meet the same standards as tests provided by the NHS or certified private clinics.