Contact dermatitis is a condition that develops when the body’s immune system reacts to a substance that comes into contact with the skin. It primarily develops as a rash, and usually after the skin has been in repeated contact with the trigger substance. The most important step is to find out what is causing the rash or the symptoms in order to be able to treat them effectively.

One very common trigger is nickel, which is found in earrings, belt buckles, the buttons on jeans and many bits of metal that are used in garments. Alternatively, it could be perfume, rubber or hair dye that causes the problem

There are two types of conditions: Allergic Contact Dermatitis (ACD), which is the most common kind, and Irritant Contact Dermatitis (ICD).

The most common allergens include:

Nickel Fragrances

Rubber

Some plants

Formaldehyde

Hair chemical

People with a tendency for asthma, eczema and hay fever develop irritant contact dermatitis more easily than others, and this tendency does run in families.

Itching of the skin is the most common symptom, and this can be intense. Sometimes the skin becomes sore, and painful cracks can develop over the backs of the fingers when dermatitis affects the hands.

The most common areas which contact dermatitis can occur are the hands, arms, face and legs. During a flare up, contact dermatitis inflames the skin surface making it look red and scaly. Sometimes, tiny water blisters develop and these leak fluid when scratched. When the contact dermatitis is less active, the skin looks thick and dry, and painful little cracks can form over the joints.

Two main groups of things in the environment cause contact dermatitis: irritants and allergens. Irritants are substances like detergents and solvents that strip the skin of its natural oils, and cause dermatitis to develop if contacted frequently and without skin protection. When this happens, the skin changes are known as an irritant contact dermatitis. The most important factor in causing this type of contact dermatitis is the number of irritants to which you are exposed. It is particularly common in people who do a lot of wet work, for example, nurses, hairdressers, those who work in bars, and those in the catering trade. Allergens are things to which your immune system can develop a specific reaction after you have come into contact with them. Examples include substances such as nickel, rubber, and perfumes or preservatives used in some creams and cosmetics. This type of dermatitis is called allergic contact dermatitis. It is not known why some people who are exposed to these allergens develop it while others do not. Sometimes substances such as proteins in fruit and vegetables can cause an immediate allergic reaction leading to itchy skin swellings known as contact urticaria (hives), which in turn can aggravate your dermatitis. Contact dermatitis cannot be caught from or spread to other people.

Nickel

Nickel is one of the major triggers of contact dermatitis and unfortunately is found in a variety of products. Many chrome-plated objects contain enough nickel to produce a reaction in sensitive people. Stainless steel also contains nickel, however, it is bound in such a way that the stainless steel is safe for most nickel-sensitive individuals. Earrings containing nickel can cause earlobe dermatitis, a very common problem. For this reason, only sterile stainless steel needles should be used for piercing. You should also only wear nickel-free earrings for at least three weeks after the piercing. Clothing accessories made of nickel such as buckles, zippers, buttons and metal clips can also cause dermatitis. The list of goods to avoid is endless. The good news is, in most cases, it is possible to substitute with accessories made from nickel-free materials. Sweating increases dermatitis in nickel-sensitive people. During the summer, items containing nickel can cause an itchy, prickly sensation within fifteen to twenty minutes of touching perspiring skin and a rash may appear within a day or two.

Latex

Latex (rubber) products often cause allergic contact dermatitis (ACD). This is a particular problem for nurses because most of the gloves they have to wear when working with patients are made of rubber. The condition can cause immediate allergic reactions, including itching or burning at the point of contact with the skin. Some people also experience itching and streaming eyes and, occasionally, shortness of breath. This is more common in people who wear tight-fitting rubber gloves, such as medical workers and hairdressers etc. Rubber gloves may also cause dermatitis on the skin of the hand under the glove. Even leather shoes can cause a problem: elements in the rubber that is used to hold the shoes together can provoke a reaction. If possible, try to find shoes without rubber in them at all. Of course, avoiding the allergen altogether is the best strategy for combating the discomfort of a reaction, but if you have to wear protective gloves, opt for vinyl (PVC) ones. If you have no choice but to wear latex gloves, ensure that they are non-powdered and always wear cotton gloves underneath.

Hair Dyes

There has been a lot of controversy in recent years over permanent hair dyes and the chemicals they contain. One of the key ingredients is paraphenylenedeamine (PPDA), which is currently found in two-thirds of hair colourants, and has to be mixed with an oxidising agent, such as peroxide, before application. Research published in the British Medical Journal in 2007 warns that the chemical can lead to dermatitis on the face and in severe cases can even cause facial swelling. People allergic to PPDA really should not use any permanent hair dyes. About one-quarter of the people allergic to it are also allergic to ingredients in semi-permanent dyes. If you are not sure about your reaction, always follow the package instructions and test an area of skin before you use the dye for the first time. One alternative for sufferers is to look at organic hair dyes, which are becoming very popular, as they don’t contain PPDA.

Chromates

Compounds containing chromium, called chromates, are a common cause of allergic contact dermatitis (ACD) in construction workers and others who have constant contact with cement, leather, paints and anti-rust compounds. Exposure to chromium is common in jobs in the automobile, welding, foundry, cement, railroad and building repair industries, but sometimes goes unnoticed – or ignored – by employers. According to some statistics, skin disorders comprise more than 45% of all occupation-related diseases. Among all cases of occupational dermatitis, allergic contact dermatitis accounts for about 30%.