Cause of dermatitis –
The most common cause of dermatitis (skin inflammation) is an allergic reaction to a substance which comes in contact with the skin and irritates it. Many of the eruptions on the face, neck and other areas of the body are allergic reactions to substances applied to the skin (cosmetics), to substances in clothing (dyes, laundry detergents), and to the active ingredients in household cleaning products and to the nickel found in jewelry.
Special tests can determine the exact cause of an allergy. If contact with the offending substance is avoided, the dermatitis will disappear by itself.
There are two different forms of dermatitis which appears as a result of contact with a certain substance:
The inflammation is caused by direct contact with a strong substance such as an acid, or by exaggerated use of a harsh soap. Contact with these substances results in an irritation regardless of who the person is, and is not related to an allergic tendency.
The only way to prevent this kind of dermatitis is to wear gloves or to avoid dealing with the substances.
2) The inflammation is an allergic reaction called contact dermatitis and occurs only in the small percentage of the population which is naturally sensitivity to them.
Allergic reactions can also be produced by the ingestion of certain substances. Some cases of allergic dermatitis affecting the entire body are caused by various drugs and medicines, especially those belonging to the penicillin and sulfa groups. In a small number of cases certain foods produce allergic reactions, especially fruits, eggs and fish.
A rash caused by substances which come in contact with the skin usually itches and is flat and red. In some cases blisters or “weeping” appears on the red areas. If the rash continues for an extended period of time the skin may thicken and crack. Such an allergic reaction will usually occur within two or three weeks after the first contact with the irritant. After the second contact, the allergic reaction usually appears in two to four days. In a small percentage of cases an allergic reaction to cosmetic products can appear after months or even years of exposure.
The red, itchy area can appear anywhere on the body, depending upon the point of contact with the irritant. An allergy to the nickel found in earrings appears on the earlobes, while an allergy to a substance found in a watchband appears on the wrist under the watchband.
Often the rash appears in unexpected places on the body and the cause is more difficult to determine. For instance, an allergy to nail polish may appear on the eyelids but not on the hands. The reason is that most people touch their eyelids without being aware of it, and since the skin of the eyelids is thinner than that of the hands, an allergy to nail polish or even to hand lotion will appear on the eyelids, and only infrequently around the fingernails or on the hands.
THE MOST COMMON CAUSES OF SKIN ALLERGIES-
Nickel: Nickel is a metal found in many products, especially those plated with a chrome-nickel alloy or those made of stainless steel, of which nickel is one of the components. Many earrings not made of gold contain nickel and cause dermatitis in people allergic to it. The metal buttons on jeans and belt and watchband buckles also contain nickel and can cause allergic reactions in sensitive people. Since perspiration dissolves a small quantity of the nickel found in various products, these reactions are more common in summer.
Rubber: Rubber is a frequent cause of allergic reactions. An allergy to rubber appears as an itching red rash which can manifest itself a few minutes after contact with an article containing rubber. Most of these reactions occur in people who use rubber gloves, among them doctors and nurses who wear gloves made of latex. People who have been diagnosed as allergic to rubber and to rubber-bearing products are advised to wear vinyl gloves instead, since these to not produce allergic reactions.
Hair Dyes: Some people are sensitive to hair dyes. A common cause is the pheraphenylan diamine, one of the ingredients found in hair dyes.
Chromates: Chromates are substances common in cement, shoe leather, matches, paints and some anti-rust preparations. Welders, construction workers and shoe makers are readily exposed to chromates and can develop allergies to products containing them.
Cosmetics: The wide range of cosmetic products that can be bought today enables us to beautify our hair and nails. Remember, however, that these products can cause unwanted side effects such as allergic dermatitis, increased sensitivity to the sun, lesions resembling acne, etc., which should be diagnosed early to prevent continued damage to the skin.
The most common cause of cosmetic allergy is caused by the fragrances present in cosmetic products. More than five thousand such fragrances are in use today and are found not only in cosmetics which are applied or sprayed onto the skin but in other common household items such as toilet paper, paper towels, soaps, detergents and fabric softeners.
Some of the fragrances, especially those used in men’s after shave lotions until a few years ago, cause increased facial skin sensitivity to the sun, which can lead to hard-to-cure chronic skin inflammations or to brown splotches on the skin. Allergy tests can determine the exact cause of this sensitivity.
Preservatives are found in the overwhelming majority of cosmetic products. Their role is to prevent bacteria and fungi from contaminating the product. These preservatives often cause rashes and are the second most common cause of allergic reactions to cosmetics.
A small number of side effects has been noted as a result of the use, welcome as it is, of sun blocks. These allergic reactions appear as local redness or itching. They used to be caused by an ingredient called PABA, which is no longer used in such preparations; today they are caused by sun blocks containing oxybenzone.
There have been infrequent reported cases of skin irritations caused by toothpaste. In these few cases, sensitivity to toothpaste or mouthwash appears as an itchy red area around the lips. In a few cases allergic reactions to the fluoride in toothpaste have caused lesions resembling the pustules of acne around the lips.
Shaving creams and after shave lotions can cause irritations or allergies, chiefly because of the fragrances they contain. One of the most common such fragrances in use during the nineteen sixties and seventies was called “musk ambrette,” and caused severe skin inflammations which worsened upon exposure to the sun.
Certain cosmetic products contain hypoallergenic ingredients which cause fewer allergic reactions than ordinary cosmetic products. Although the chance of developing an allergic reaction to one of these substances is relatively small, they are not perfect and do cause such reactions in some of the people who use them.
HOW TO FIND THE CAUSE OF CONTACT DERMATITIS
In most cases diagnosing the exact cause of an allergy requires a great amount of knowledge and information. If the locality of the allergy does not point to any specific cause, the dermatologist will perform a special test called a patch test. This test requires three visits to the dermatologist’s office. During the first visit the dermatologist sticks a series of special adhesive tapes to the patient’s back. These pieces of tape have been impregnated with the most common allergy-causing reagents. The test can also include substances habitually used by the patient, such as skin creams, soaps and after shave lotions.
48 hours later the patches are removed and reactions are examined, and 48 hours after that another examination is performed. Judging by the reactions, in most instances the dermatologist can determine which substances the patient is sensitive to.
If the dermatologist diagnoses the cause of the allergy, he can advise the patient to replace the offending substance with one to which the patient is not sensitive, or he can advise a different course of treatment. Once contact with the irritant is avoided, the rash can easily be treated with the proper medication and will disappear.
HOW TO PROTECT YOUR HANDS AGAINST CONTACT DERMATITIS ?
Redness, sensitivity and cracks in the skin of the hands develop for many reasons. One of the most common is a reaction to substances with which the hands come in contact.
During the day we all touch irritating substances such as dishwashing liquids and detergents, oils and acids. The skin of people whose work includes cleaning is usually inflamed as a direct result of being irritated by these products and not as the result of an allergic reaction.
1) Wear rubber gloves or thick vinyl gloves (the best ones are those lined with cotton) while washing dishes, cleaning the house or when coming in contact with any harsh substance. Buy several pairs of such gloves, keep them in various places around the house and use them whenever necessary. After use, turn them inside out and allow them to dry thoroughly.
2) Since there are several vegetables which contain substances liable to irritate the skin, it is wise to wear gloves when peeling lemons, oranges, potatoes, and especially when touching and cutting tomatoes.
Share on Facebook
Did you like this? Share it: