Allergies: Symptoms, Causes and Diagnosis

Allergies are a common health concern that affects a significant portion of the population. According to the World Health Organization, allergies impact up to 40% of the global population, and their prevalence among adults grows daily.

Allergies can cause a variety of immune system reactions that can range from mild nuisances to life-threatening conditions. As their prevalence continues to grow, understanding the reasons behind allergic reactions becomes paramount. 

What are allergies?

An allergy is an abnormal and exaggerated immune response of the body to typically harmless substances, known as allergens. Allergens can include various materials, such as pollen, pet fur, food, insect venom, and medication. 

These allergens can sometimes trigger an extreme allergic reaction known as anaphylaxis. In this severe reaction, the body showcases acute allergic symptoms like inflammation, skin reactions, and difficulty breathing. Anaphylaxis needs immediate treatment since it can become life-threatening if not dealt with in time.   

Signs and Symptoms of Allergies  

When your body goes through an allergic reaction, your immune system releases chemicals, most notably histamine. It is responsible for the symptoms you see during the response, like redness, inflammation of body organs, or itching.

Your body can manifest various symptoms based on the type of allergic reaction. Let us have a look at the most common signs and symptoms of different allergies:

Food Allergy

One of the most common allergies among humans, food allergies occur when your body considers specific food items as allergens. An allergic reaction caused by food can occur within minutes of consuming that item and can display symptoms like:  

1. Hives on skin
2. Inflammation of lips, throat, or other body parts
3. Diarrhoea
4. Anaphylaxis

Inhalant Allergy

Inhalant allergies occur when you inhale airborne allergens through breathing. Inhalant allergies are caused by two types of allergens: perennial and seasonal allergens. Perennial allergens can cause allergic reactions at any time throughout the year. Meanwhile, seasonal allergens are only found in a specific season, giving rise to seasonal allergies.

Some common symptoms of inhalant allergies are:  

1. Runny nose 
2. Watery eyes 
3. Sneezing 
4. Itchy eyes and nose 

Drug Allergy

Some people can exhibit allergies to certain medicines. These medicines can be herbal, OTC, or even prescription. This is why many doctors cross-check patients for drug allergies before prescribing certain medications. Some common symptoms of drug allergy are:  

1. Hives on skin
2. Itching
3. Anaphylaxis
4. Skin Rash 

Skin Allergy

Skin allergy types are caused when a person comes in direct contact with harmful chemicals or metals. Products containing latex, poison ivy, and nickel are also known to cause skin allergies. Some common skin allergy symptoms are:

1. Hives on skin
2. Irritation  
3. Redness and itchiness 
4. Burning sensation 
5. Swelling of body parts   

Allergic Rhinitis

Allergic Rhinitis, more commonly known as hay fever, is an allergic reaction that occurs when you come in contact with airborne allergens like pollen, pet fur, moulds, or tiny insects. It is a common allergy and can display the following symptoms:

1. Runny nose 
2. Dizziness 
3. Congestion 
4. Itchy eyes and nose 
5. Watery eyes 

Insect Sting Allergy

Insect stings are also responsible for some pretty nasty allergic reactions. Typically, insects like bees, wasps, hornets, and ants are responsible for inducing allergies in humans. Some common symptoms of an allergic reaction to insect stings include:  

1. Swelling of mouth, lips, and throat
2. Hives on skin
3. Difficulty in breathing and swallowing
4. Rapid pulse
5. Dizziness
6. Anaphylaxis 

Causes of Allergies 

Allergies are complex and can be influenced by genetic, environmental, and lifestyle factors. Here are some commonly occurring causes of allergies:  

1. Genetic Predisposition

Family history plays a significant role in the development of allergies. If parents or close relatives have allergies, an individual is likely to develop allergies. 

2. Changes in Lifestyle

Untidy surroundings, polluted air and water, and reduced outdoor activities may contribute to the rise in allergies. Research shows that urbanization and changes in lifestyle affect the balance of immune responses in the body, causing inflammation and allergies among general populations.  

3. Diet

Having a poor diet, such as the consumption of highly processed foods and a lack of diverse nutrients, may contribute to the development of allergies. Some studies suggest that breastfeeding and introducing certain foods early in life might help reduce allergy risk. 

Allergy Diagnosis

If you think you might have an allergy, having it checked out with an Allergist is essential. Some standard ways of diagnosing allergies include: 

• Skin Prick Test: In this test, the doctor tries to identify the allergen causing a reaction in your body. This is done by introducing a small number of common allergens into a tiny region of your skin. If that area reacts, you can determine the allergen causing you trouble.
   
• Blood (IgE) Test: In this allergy test, a blood sample is taken to study the level of antibodies produced in response to specific allergens. This test, however, is not as sensitive as the Skin prick test.  

Allergies are common immune system responses to normally harmless substances that affect a significant portion of the population. Understanding the causes, symptoms, and diagnosis of allergies is crucial for effective management and treatment. 

If you are allergic to something, avoiding it at all costs is best. While allergies cannot be cured completely, medications are available that relieve symptoms. So, consult an allergist to know the medications that can help you in emergencies. Carrying an Epinephrine Auto-Injector is also advised if your allergic reactions tend to become serious.