Skin Allergies 

• Symptoms: Severe rashes, hives, swollen eyes, burning, itching, eczema, sore throat
• Causes: Animal products, mould, insect stings, drugs, plants, latex, various metals
• Risk Factors: Age, family history, asthma
• Severity: Mild to severe 
• Which doctor to consult: Dermatologist

Overview

An allergy is the body's way of negatively reacting to a substance or allergen it flags as harmful. These allergens include pollen, pet hair, insect stings, latex, certain foods, etc.

The immune system generally adapts to its immediate surrounding. If a foreign substance enters the body, it should be able to detect whether the substance is harmful or not.

However, the immune system of people with allergies fails to do that for allergens, triggering a reaction. For instance, if pollen enters the body of a person allergic to pollen, his/her body won't understand that the allergen is harmless. The immune system fires up and releases antibodies immediately, paving the path for symptoms.

When the human body detects an allergen, the immune system will start pumping out allergic antibodies IgE. Consequently, the human body produces a chemical known as histamine, which gives rise to all skin allergy symptoms.

If an allergic person comes in contact with allergens, he/she might experience a reaction within minutes. So, if a person feels that he/she has skin allergies, he/she must stay away from the following possible causes and allergens:

• Sunscreens 
• Cleaning products 
• Bug sprays 
• Certain plants (e.g., poison ivy)
• Latex 
• Certain metals (e.g., nickel)
• Certain chemicals

When to Consult a Doctor?

If an individual is showing allergy symptoms like rashes or sores, he/she must visit a dermatologist as soon as possible. A skin rash may announce the onset of an allergy.

Although the rash might not be severe, there is a chance that it hints at an underlying medical condition.

If one suspects that he/she has skin allergies, he/she must look out for the following signs and symptoms:

• Heavy fever accompanied by a rash
• Rash all over mouth, eyes, and genitals
• Painful and itchy rash
• Rash starts spreading rapidly 
• Open sores (rash transforms into a blister)
• Rash spreads over the entire body

Diagnosis

Doctors will initially examine the patient's skin to examine the symptoms. Then, they will perform a comprehensive analysis and ask the patient about the products he/she currently uses. This includes soaps, detergents, and other skincare products.

First, the doctor might suggest a patch test to determine the cause of dermatitis. The patch will contain many allergens in the form of tiny dots. This patch is pasted on the patient's back and kept for 48 hours. The patch must not get wet in this timeframe, so the patient must not sweat and take bath.

Once the 48 hours is over, the patch is removed, and the location of the patches is marked. This helps during the final evaluation, which is done 72 to 96 hours after the patches are applied. If the patient's skin has reacted to any patches, the doctors will note the reaction. This will help them determine what allergens the patient must avoid.

Furthermore, this test is painless and doesn't involve needles poking into the patient's skin. Here are a few other tests that are performed to determine the presence of a skin allergy:

• Skin Prick Test

Also known as the puncture test or scratch test, the skin prick test essentially introduces over 50 different possible allergens to the bloodstream to check for multiple allergies simultaneously. This list of allergens generally includes certain foods, pollen, mould, pet dander, etc.

The skin prick test is carried out on the arm of adults and the backs of children. Remember that this test isn't as painful as it looks since the needles don't even penetrate the skin's surface thoroughly. As a result, there won't be any bleeding after the test, and the patient will only experience mild discomfort.

Once the pricking is done, the doctor will clean the site with rubbing alcohol and mark them. Post this, a drop of allergen extract is applied at the test site; if the skin shows a reaction, the allergen is determined.

Additionally, two other substances are rubbed on the test site:

1. Glycerine: Most peoples' skin don't react to glycerine. However, if it does, the patient has very sensitive skin, and the doctor will perform the allergy testing much more cautiously.

2. Histamine: Histamine is the chemical responsible for an allergic reaction from inside the body. Therefore, most peoples' skin will react after rubbing histamine on it. However, if it doesn't, then there is a chance the skin might not respond to the allergen, even if an individual has an allergy against histamine.

• Skin Injection Test

The skin injection test is generally done to check if an individual is allergic to penicillin or insect venom. The test follows a similar procedure to the one above, except it uses an injection instead of a prick.

The doctor will wait 15 minutes for an allergic reaction to confirm the results.

• Allergy Blood Test

The allergy blood test, as the name suggests, draws a blood sample from the patient, which is then checked for its immunoglobulin (IgE) levels. If a person’s IgE levels are higher than usual, there is a chance that he/she is allergic to something. The test generally checks two primary things, namely:

1. Total IgE level: This measures the whole IgE antibodies present in the patient's bloodstream.

2. Specific IgE level: A single allergen is introduced into the patient's bloodstream and the test measures the IgE level response to each allergen.

Treatment:

Here are a few treatment options for skin allergies:

• Home Care

Home care for skin allergies depends on what is causing the patient's allergy. Generally, the first step to starting home care for skin allergies is to avoid the allergens altogether. If an individual comes in contact with allergen, he/she can use calamine lotion, an oatmeal bath, or a simple cold compress to eliminate the itching.

Furthermore, if the allergic reaction is in a sensitive area, the doctor will prescribe a steroid cream to be used in the right amounts for maximum relief and efficiency.

• Medication

Allergy medication primarily consists of antihistamines, which counteract the effect of the chemical histamine released during an allergic reaction. These antihistamines can either be prescription medications or over-the-counter drugs. The doctor will prescribe allergy medication based on the severity of the patient's allergic reaction.

The various drugs used to battle skin allergies include:

• Antihistamines 
• Cetirizine 
• Corticosteroids 
• Decongestants 
• Leukotriene modifiers 
• Loratadine 
• Cromolyn sodium

If nothing else is easing the symptoms, the drug Singulair is used as the last resort. This drug is avoided since it can cause mood and behavioural changes, including suicidal thoughts, mental disturbance, and so on.

• Alternative Treatment

An alternative treatment method for allergies is immunotherapy. This treatment method requires the patient to take numerous injections over a few years. This will help the patient's body to get used to the allergy and keep the symptoms from returning in the future.

Risks & Complications if Left Untreated

Untreated allergies can cause quite a few complications down the line. The allergy symptoms and attacks might keep growing in severity and frequency. If this continues for long, the patient's immune system will weaken, leaving him/her vulnerable to complications such as fungal or bacterial infections (lungs, sinus, ears, and skin).

Furthermore, the patient will be exposed to the risk of growing allergies to other allergens. Lastly, if the patient already has asthma, then delayed treatments for allergies will worsen his/her condition and leave him/her vulnerable to intense asthma attacks.

Additional Information

Skin allergies are an extensive term that includes several conditions. Still, some infections and diseases are most common due to their triggers. This section explains such well-known allergies along with their triggers.

1. Hives

These allergies can be identified by red bumps that can often be itchy. Some potential triggers of hives are as follows:

• Insect bites
• Reaction to sweat or heat
• Sunlight
• Stress
• Tight clothing or scratching

Allergic reactions to foods like eggs, shellfish, and nuts can also cause hives. Fortunately, hives fade in some days. Individuals can also use anti-itch drugs to combat these skin infections.

2. Eczema

This condition is characterised by a rash, prominently on the arms and knees. It results from a reaction to triggers like detergents, allergens, dust mites, pollen, and humidity.
Treating this itchy inflammation is straightforward. The doctor can prescribe suitable ointment or cream for external use. Such products help reduce the swelling in affected areas.

3. Angioedema

This skin allergy can accompany hives and occurs in the skin's deep layers. 
This condition can occur when the immune system perceives a harmless material as lethal. The allergic reaction leads to the release of antibodies to attack the trigger. Symptoms like swollen eyes, mouth, and difficulty in breathing are common among people with angioedema.

4. Skin Rash

In simple terms, skin rash implies a broad spread of lesions on the outer layer. These allergies are subjective and affect millions of individuals around the globe.
Common triggers of skin rashes include allergic reactions to the following:

• Plants like sumac
• Latex
• Rubber
• Beauty products
• Contact dermatitis

Rashes are primarily red and inflamed. In some cases, bacteria, fungi, and viruses can also lead to skin rashes. Some potential causes of rashes are flea bites, impetigo, shingles, scarlet fever, and mono.
Hydrocortisone cream is the most well-known solution for treating such rashes.

5. Acne

This skin condition is not always an allergic reaction. Acne can be a result of hormonal changes in teenagers or young adults. The sebum plugs hair follicles in this skin disorder, leading to a tender bump.

However, foods like potato chips, sugary drinks, milkshakes, and cornflakes can be potential triggers. In most cases, proper hygiene and avoiding irritants can reduce the onset of acne.