There are various types of skin allergies and they usually occur when some foreign body invades our skin. For instance, when anything comes in contact with your skin, your immune system may consider it to be an invader. At times, the immune system overreacts, sending antibodies to combat the invading foreign body. Consequently, reddish, itchy rashes emerge on the skin surface that has been exposed to the foreign body or substance. In addition, you may also develop allergic reaction to any substance from the air settling on your skin. These substances ma include pollens, powders, chemical sprays, cigarette smoke or any fiber. Scientifically speaking, such a situation is known as airborne contact dermatitis. This usually occurs on one's head, eyelids and neck. Doctors may find diagnosing such a condition quite difficult, as it does not appear to be different from any other type of substances.
Skin allergies and rashes are itchy and they appear in various forms. Nevertheless, all itchy rashes are not associated with skin allergies. Some of the most widespread forms of allergic skin rashes are discussed below in brief.
Allergic contact dermatitis: This condition occurs when one's skin is directly exposed to any allergen. For example, when you endure a nickel allergy, your skin actually comes in contact with any jewellery that may even have slight nickel content. This condition may result in the affected skin area becoming reddish, scaly, bumpy, itchy or even swollen.
Allergic contact dermatitis may also occur when you skin comes in direct contact with poison oak, poison ivy and poison sumac. An oily substance that coats these plants is responsible for the reddish, itchy rashes. Such allergic reactions may actually occur when you touch these plants and the oily substance or when the substance touches your clothes. Coming in direct contact with even pets and gardening tools that are exposed to this oily substance may result in allergic contact dermatitis.
Hives are basically a type of skin inflammation that is activated when our immune system discharges histamines. As a result, the small blood vessels or capillaries start leaking, resulting in swollen and inflamed skin. When the deep layers of the skin also become swollen, the condition is known as angioedema. Urticaria occurs in two different types - chronic and acute. Usually allergy tests are not effective for diagnosing chronic urticaria, as the condition is seldom caused by particular triggers. It has been observed that chronic urticaria may continue for several months or even years. Usually, acute urticaria emerges following consumption of specific foods or when any individual is exposed to a specific trigger. At the same time, this condition may occur due to non-allergic causes like exercise or heat. In addition, foods, medications or insect bites are also sometimes responsible for acute urticaria. Although hives may be usually uncomfortable and at time painful, they are not infectious.
When one is diagnosed of angioedema, he/ she will suffer from swelling deep inside the skin layers. Often, this condition occurs alongside hives (urticaria). On several occasions, angioedema may crop up in soft tissues like the mouth, eyelids or genitals. If one endures this condition only for a brief period, for instance for few minutes to some hours, it is called acute. In most cases, acute angioedema is attributed to an allergic reaction caused by foods or medications. On the other hand, chronic angioedema is a recurrent condition. It usually returns after a prolonged period. Generally, chronic angioedema is not attributed to any specific cause.
Although rare, hereditary angioedema (HAE) is a severe genetic health condition that involves swelling in different parts of the body, counting the face, hands, feet, airways and the intestinal walls. Since hereditary angioedema (HAE) does not respond to treatment with adrenaline or antihistamines, it is necessary to consult a specialist.
Itching without rash is a very common problem experienced by several people. In such cases, people experience itching, but there is no skin rash. In medical terms, such type of itching is called pruritus. The symptoms associated with this condition may be a manifestation of a skin disorder or any type of internal disease.
If pruritus occurs throughout the body, it may also be a sign of a skin disorder, or be a result of metabolic problems like iron deficiency or thyroid disease. Even various different types of medications can be responsible for pruritus, especially palliatives such as codeine and morphine.
On the other hand, if the itching is confined to a particular area of your body, it is possible that a disease process is restricted to the skin. In fact, the body area that itches very frequently gives an indication regarding the reason for such itching without skin rash.
It is worth mentioning here that allergies are one of the most common skin conditions that are managed and treated by allergists or immunologists. They are specialized physicians who have expertise in correctly diagnosing the condition and undertake the right treatment to provide relief from the bothersome, often painful, symptoms.