What is my body trying to do when it has an allergic reaction?

Summary: Allergic reactions occur when the immune system overreacts to harmless substances like pollen, food, or insect stings, triggering symptoms from sneezing to life-threatening anaphylaxis. The body's release of histamine causes these symptoms, and treatment depends on severity, ranging from antihistamines for mild reactions to adrenaline for severe ones. Prevention involves identifying and avoiding triggers, keeping medication handy, and seeking prompt medical help when symptoms escalate. Understanding your body’s response is key to managing allergies effectively.

Allergic reactions occur when the immune system mistakenly identifies a harmless substance as a threat. This can include pollen, pet dander, certain foods, or insect stings. Your body then launches a defence, which results in the symptoms associated with allergies. But what exactly happens during an allergic reaction, and how can you manage it effectively?

What does your body do during an allergic reaction?

When an allergen enters your body, your immune system perceives it as harmful and releases immunoglobulin E (IgE) antibodies. These antibodies trigger the release of histamine and other chemicals from mast cells, leading to symptoms such as itching, swelling, sneezing, or in severe cases, anaphylaxis (a life-threatening type of allergy). The body’s response depends on the type of allergen and the individual’s sensitivity. For example:

• Pollen allergies may cause sneezing, runny nose, and itchy eyes.
• Food allergies can lead to digestive issues, swelling, and even difficulty breathing.
• Insect stings may result in localised swelling or full-body anaphylaxis.

Also read: Can seasonal allergies make you feel sick?

Mild vs severe allergic reactions

Allergic reactions range from mild to life-threatening:

• Mild reactions: Symptoms may include sneezing, watery eyes, skin rash, or mild swelling. These typically resolve with antihistamines or avoidance of the trigger.
• Severe reactions (Anaphylaxis): Symptoms include difficulty breathing, swelling of the throat, dizziness, and a rapid drop in blood pressure. This requires immediate medical attention and the administration of adrenaline, commonly via an EpiPen.

How do you calm an allergic reaction?

Managing an allergic reaction depends on its severity:

• Mild reactions: Take an antihistamine, remove exposure to the allergen, and apply a cold compress to soothe irritated skin.
• Moderate reactions: If swelling or discomfort increases, a doctor may prescribe corticosteroids or stronger antihistamines.
• Severe reactions: Use an adrenaline injector immediately and seek emergency medical help.

Why does my body overreact to allergens?

Your immune system is designed to protect you from harmful invaders such as bacteria and viruses. However, in individuals with allergies, the immune system mistakenly identifies harmless substances as threats. Genetic predisposition plays a role, as does prolonged exposure to certain allergens from a young age.

What to do when allergy triggers?

• Remove yourself from the allergen if possible.
• Take antihistamines if symptoms are mild.
• Use an asthma inhaler if allergies trigger breathing difficulties.
• Administer adrenaline if symptoms of anaphylaxis appear and seek emergency care.

What not to do if a person is having an allergic reaction

• Do not ignore symptoms, especially if they escalate.
• Do not delay medical treatment if breathing difficulties occur.
• Do not administer food or drink to someone experiencing anaphylaxis.
• Do not assume symptoms will resolve on their own if they are severe.

How long does it take for an allergic reaction to clear up?

• Mild reactions: Typically resolve within a few hours to a day with antihistamines.
• Moderate reactions: May take a couple of days if swelling or rashes are involved.
• Severe reactions: Anaphylaxis is an emergency, and even with treatment, recovery may take hours to days, often requiring hospital monitoring.

Tips to prevent allergic reactions

• Identify and avoid known allergens.
• Keep antihistamines or prescribed medication on hand.
• Using allergy-proof bedding and air purifiers for airborne allergies may help to alleviate symptoms for some sufferers.
• Be cautious with new foods if you have a history of food allergies.
• Wear a medical alert bracelet if you have a severe allergy.

Also read: Tips for seasonal allergy sufferers: GP-recommended 

When to contact a medical professional

Seek medical help if:

• You experience difficulty breathing, swelling of the throat, or dizziness.
• Allergy symptoms persist despite taking antihistamines.
• You have recurrent or worsening reactions.

Can a telehealth doctor help?

Yes, telehealth services can be a convenient way to manage allergies:

• Instant consult online: You can discuss symptoms and receive guidance on management from a doctor without leaving home.
• Doctor's referrals online: If your symptoms require specialist care, a telehealth doctor can refer you to an allergist.
• Quick online scripts: If antihistamines or other medications are required, prescriptions can be sent to your local pharmacy.
• Medical certificates Australia: If an allergy flare-up affects your ability to work or attend school, a telehealth doctor can provide a medical certificate.

How can Hola Health’s online doctor help via telehealth?

Hola Health’s online doctors provide expert advice and treatment options for managing allergies. Whether you need a prescription, a referral to a specialist, or guidance on avoiding allergens, our telehealth service ensures you get the care you need quickly and conveniently. Book an online consultation today to take control of your allergy symptoms from the comfort of your home.