The skin is a natural defense against harmful agents in the environment. It is packed with immune cells that attack viruses or bacteria that latch onto the skin. When these defense cells detect any harmful or potentially harmful substance, it mounts up an immune response against it. This leads to the formation of rashes, which may be itchy.
Itchy skin and rashes can be very disturbing and even embarrassing as they may get us to scratch in public places. This symptom may be localized to one area of the body or generalized, it may also be constant or recurrent, often affecting one’s appearance and functionality. Your itchy rashes can be caused by so many different conditions and until the exact cause is figured out, a solution may be far-fetched.
Causes of Itchy Skin Rashes
As said, most rashes are a result of the immune system trying to defend the skin from invasion by potentially harmful substances and there are many causes of this, which include:
Allergic reactions may present with raised red bumps or blisters on the skin. These occur in response to harmless agents called allergens that the immune system considers harmful.
Examples of allergens include clothing, pets, soaps, molds, latex, nickel, and even food. If you experience raised, red bumps or spots in certain parts of your skin upon skin contact with jewelry, certain clothing, or after eating foods such as nuts and seafood, you are likely having an allergic reaction. Symptoms of an allergic reaction can appear within seconds, minutes, or hours following exposure to the allergen and in severe cases may cause the skin to peel off.
Treatment of allergies includes topical corticosteroids to lower the skin inflammation and oral antihistamines to suppress the itch. You may also need moisturizers or emollients to keep your skin moist as dry skin worsens symptoms of allergies. These medicines are readily found over-the-counter without a doctor’s prescription.
Hives, also known as urticaria, occurs as a sudden outbreak of raised pale red wheals or bumps on the skin, often in response to allergens but may occur without any triggers.
Hives can occur in different parts of the body including the face, ears, and lips with rashes of various sizes, lasting several hours before spontaneously resolving. Hives occur in response to the release of a chemical called histamine into the skin. Factors that stimulate histamine release include insect bites, certain foods (including berries, chocolate, eggs), and certain medicines. Non-allergic triggers including exercise, sunlight exposure, and extremes of temperature can also trigger hives.
While acute hives are triggered by these factors, chronic hives – which lasts more than six weeks – typically occur in response to diseases such as hepatitis, cancer, or thyroid diseases.
The best way to treat hives is to identify and avoid the trigger. In the event that you develop the symptoms, your doctor may recommend antihistamines to improve your symptoms. Wearing loose-fitting clothes and applying cool compresses on the affected areas may also help improve the itch.
If these do not provide significant relief, your doctor may prescribe an oral corticosteroid or drugs that modulate the immune system such as omalizumab.
Eczema, or atopic dermatitis, is the commonest cause of skin rash in children. It appears as red, rough, cracked, inflamed patches of skin, which are often intensely itchy. The pattern of the symptoms, however, depends on the age of the child. In children under 2 years, the rashes are more prominent on the scalp and cheeks while children above 2 years have it more commonly on the neck, wrists, and the back of the elbow and knees.
In adults, the rashes appear commonly in the creases of the knees and elbows, around the eyes, and on the face. The rashes are also more scaly in adults and the itch more intense than in children. Although children outgrow eczema, some children still experience it into adulthood where the skin remains constantly dry and easily damaged.
Eczema, as with other forms of atopy – a genetic predisposition to develop allergic diseases – is triggered by environmental factors such as skin irritants (detergents, soaps, shampoos), allergens, and stress. Hormonal changes in pregnancy and menstruation can also trigger eczema.
Although there is no cure for eczema, there are some medications you can use to relieve the symptoms. These include topical corticosteroids to reduce the inflammation and oral antihistamines to eliminate the itch. Severe cases may be treated with phototherapy and immune suppressants.
Furthermore, home remedies to improve the symptoms of eczema include avoiding eczema triggers, taking lukewarm baths, applying moisturizers or emollients after bathing, using a mild bathing soap, and avoiding extremes of temperature.
Bug bites may leave a small bite mark that is surrounded by areas of red patchers or may trigger a bigger rash that is extremely itchy. Both are caused by formic acid injected into the skin when an insect bites.
Common biting insects include fleas, bedbugs, midges, mosquitoes, and ticks. The symptom pattern and severity depends on the type of insect and the individual’s sensitivity. For example, mosquito bites may cause small raised, red bumps on the site of bite, but scabies, which is caused by a type of mite, triggers a more generalized pattern with extremely itchy rashes mostly in skin folds.
Some of these insect bites trigger an allergic reaction with hives and blisters on different parts of the body.
Treatment of bug bites requires the identification of the bug and finding its source. If the insects come from a pet, you may need to get the pet to a vet. Essentially, insect control measures will be necessary to prevent further incidences.
Although itchy rashes from insect bites resolve spontaneously within a few days, you may also apply a cold compress or topical corticosteroid and take oral antihistamines to reduce your symptoms.
Fungal infections cause itchy rashes in different parts of the body including the feet and toe webs (Athlete’s foot), groin area (jock itch), scalp (tinea capitis), and nails (onychomycosis). These infections often present with redness, blisters, and sores in the affected area.
These infections are caused by fungi, which grow best in areas of the body that are warm and moist such as shoes, swimming pools, floors of public showers, and locker rooms. Furthermore, in warm, humid climates, these fungi grow rapidly and are easily contracted and spread between people.
Treatment of fungal infections includes the use of topical or oral antifungal medications and taking steps to avoid excessive moisture in the body.
Itchy rashes are always a nuisance to us and there are several conditions that may be causing yours. Correctly identifying the cause helps you to use appropriate treatment options and avoid a recurrence.