Contact Allergy (Contact Dermatitis) – Causes, Symptoms & Treatment

Contact allergy (contact dermatitis)

contact allergy is also known in medicine as allergic contact eczema or contact dermatitis . All terms mean one and the same disease.

What is a contact allergy?

contact allergy , allergic contact eczema or contact dermatitis is an allergic skin reaction that occurs when there is direct skin contact with an allergenic substance (allergen).

Typically, the allergens are substances that the affected person deals with on a regular basis. This can be in the private sphere as well as often in professional life. Artificially produced substances and natural substances such as plants or parts of plants come into consideration as allergens.

Contact dermatitis does not occur on first contact with the allergen. The formation of eczema occurs as a delayed reaction of the immune system some time after contact. In the therapy of contact dermatitis, avoiding contact with the triggering substance is the decisive factor. This often means that the previous job or a long-standing hobby can no longer be practiced.


The causes of a contact allergy can be found in a hypersensitivity to substances that can cause an allergic reaction through direct physical contact . The allergy-triggering substances are different for each person.


Most of the time, however, it is substances such as flavorings in make-up or cosmetics, hair dyes and tanning agents. But also cobalt chloride, nickel sulphate, preservatives, cleaning agents, medicines, solvents and plasticizers can trigger a contact allergy.

But not only chemical substances lead to contact dermatitis in some people. Plants such as arnica and marigolds can also lead to an allergic reaction , similar to hay fever .

In women, fashion jewelry with nickel content often leads to allergic contact eczema. This is then referred to separately as a nickel allergy . Furthermore, different occupational groups may suffer more frequently from contact allergies.

Beautician: solvents, make-up, cosmetics, perfume

Hairdressers: hair dye, hairspray, hair shampoo

Bakers and confectioners: Hypersensitivity to flour

Artisans: Cement, paints, resin, glues, silicone

Caretakers or cleaning specialists: cleaning agents, cleaning fluids, room sprays

Symptoms, Ailments & Signs

A contact allergy initially causes skin changes. Within one to three days of exposure to the allergen, the skin turns red and swells around the affected area. Weeping blisters or wheals usually form , which in turn form crusts and scales. This is accompanied by increasing itching and burning.

Chronic contact eczema can develop with prolonged contact with the allergen. A callus forms, which hurts when touched and can break open after a while. Finally, a chronic skin disease sets in, through which the affected person suffers permanently from pain, itching and a strong feeling of discomfort .

In rare cases, the mucous membranes are also affected. Then there is redness, swelling and rarely ulcers in the area of ​​the mucous membranes. If the airways are involved, breathing difficulties , swallowing difficulties and acute pain reactions are possible. Occasionally, a contact allergy can bring on an asthma attack .

Contact allergy symptoms can appear anywhere on the body. Typically the hands, face, chest, neck, throat and ankles are affected. The skin reactions can spread and sometimes affect large areas of the skin. If the allergy is treated early and the allergen avoided, the symptoms usually subside within a few days.

Diagnosis & History

The development of a contact allergy takes place in two stages. The first stage is called the sensitization phase. During this phase, the body comes into repeated contact with the allergen. The exact process and the influencing factors have not been fully researched. What is certain, however, is that the process of sensitization corresponds to the processes involved in fighting off infections and that the basis for this is present in every human being.

As part of the sensitization, special cells are activated in the lymph nodes, which then multiply. In the second phase, the trigger phase, renewed contact with the allergen causes the corresponding symptoms.

The skin reactions typical of contact dermatitis usually occur two to three days after renewed contact with the trigger. This time lag often makes assignment to a specific substance difficult.

The symptoms of contact dermatitis are the same as those of other eczema diseases. At the beginning of the disease, there is redness and swelling of the affected skin area. As the disease progresses, small vesicles and nodules, the so-called papules, form. The area later dries up and becomes scaly.

If contact with the allergy-triggering substance is not avoided, the contact allergy can also take the course of chronic eczema. The complexion becomes coarser and cornifications, so-called hyperkeratoses, and cracks form.


A contact allergy can cause various reactions or symptoms. As a rule, complications can generally be avoided if the person concerned completely avoids contact with the substance in question. However, this can significantly limit the life of the patient and is not always completely possible.

For this reason, the quality of life of those affected is often significantly reduced by the contact allergy. This leads to reddening of the skin and itching in different parts of the body. As a rule, the itching intensifies when the patient scratches the area in question. Papules can also form, which also lead to reduced aesthetics.

In many cases, the symptoms lead to inferiority complexes or reduced self-esteem. Most patients are ashamed of the symptoms and therefore no longer actively participate in life. Not using a certain ingredient can also lead to depression and other mental health problems.

The contact allergy can be limited with the help of medication. However, complete healing is often not possible. There are no complications during the treatment and the life expectancy of the person affected is not reduced by the contact allergy.

When should you go to the doctor?

If the typical symptoms of contact allergy limit the quality of life, a doctor should be consulted. Symptoms can often be avoided by avoiding contact with the triggering substances. Medical advice is required when the causes of the contact allergy are unknown or when unusual symptoms and symptoms occur. Redness and itching in particular are warning signs that require clarification by a doctor. The same applies to pustules and other skin changes as well as shortness of breath, fever and circulatory problems of all kinds.

People who perceive any pustules or redness as a cosmetic blemish should consult their family doctor . Other contacts are the dermatologist or an internist . An allergist can also be consulted. The best thing to do with children with the symptoms mentioned is to see a pediatrician . Severe shortness of breath and serious cardiovascular problems are medical emergencies. The person concerned should immediately call an ambulancecall or go to the nearest hospital. In the event of a loss of consciousness, the emergency services must be alerted. The contact allergy is then treated in a hospital and the patient is provided with an allergy pass and emergency medication.

Treatment & Therapy

Contact allergies are usually treated with glucocorticoid-containing ointments when they occur acutely . Alternatively, UV therapy can provide relief. This is mostly used when the patient has other diseases that make the use of glucocorticoids impossible.

The treatment of contact dermatitis is only promising if the allergenic substance is avoided at the same time. The most important thing in the treatment of contact dermatitis is therefore to find its trigger. In some cases, there is no improvement in the eczema even after some time, despite treatment and avoidance of contact with the allergen suspected to be the cause.

It must then be assumed that there are other substances that trigger the allergy. In this case, it must be investigated which other substances could be involved. In the case of recurring contact allergies, the cause can be a lack of avoidance of contact with the allergen. In individual cases, it is often difficult to avoid the allergen if, for example, it is necessary to deal with it almost every day for professional or private reasons.

It is also possible that the symptoms are not due to a pure contact allergy. Sometimes the contact allergy and other allergic reactions or other forms of eczema occur at the same time, making diagnosis and treatment difficult.

Outlook & Forecast

The chances of finding a complete cure for a contact allergy (contact dermatitis) vary. There are prospects of healing if the cause of the contact allergy can be determined. If this is the case, professional treatment can take place. In the course of this, efforts must be made to avoid or eliminate the causes of contact dermatitis. This is often not possible or only possible to a limited extent.

In most cases, contact dermatosis is lifelong. The eczema can be kept in check by administration of corticosteroids. Irradiation with UV light can be helpful for chronic contact allergies. This can bring about an improvement, especially on the hands. However, since the immune system is involved in contact dermatitis, the prognosis is usually not so positive. Contact with the allergen can often not be completely avoided.

The chances of recovery depend on several parameters. If the triggering substance can be kept completely out of life, the healing of contact dermatitis is possible. A contact allergy is dependent on the presence of the allergen. In the case of work-related contact dermatoses, a change of occupation may be advisable or absolutely necessary.

Cortisone ointments can be sufficient for mild allergy symptoms. In the case of severe and chronic skin dermatoses, however, the affected skin can become more susceptible to bacterial or fungal infestation. It is affected by infections much more often than healthy skin.


According to the current state of research, it is not possible to prevent the development of contact allergies . It is never foreseeable which person will react to which substance with the development of contact dermatitis.

Those who are prone to allergies should try to protect their skin with protective gloves and clothing, especially when handling cleaning agents or disinfectants.

In addition, the use of pH-neutral products is recommended. Many allergen-rich products from everyday life, such as soaps, deodorants and fabric softeners can be replaced with other products. However, the development of a contact allergy cannot be completely ruled out.


The doctor treating the patient informs the patient about appropriate behavior in the context of the initial diagnosis. Beyond that, however, it only occurs in the case of acute problems. The patient bears a high degree of personal responsibility for freedom from symptoms. Scheduled follow-up examinations, as known from tumor diseases, are rare and are associated with recurring, severe symptoms.

Identifying all the triggers correctly can be time-consuming, especially in the beginning. Complications occur when the skin is attacked over a long period of time. Often only acute treatment with antibiotics helps. The transfer of knowledge is particularly important for everyday support. Those affected learn how to behave in the event of an allergic reaction.

Ointments and tablets should be available in stock. The best way to avoid the symptoms is to avoid them occurring in the first place. To do this, the patient must avoid the typical triggers or remove them from their environment. Aids such as gloves and clothing prevent infection. The patient’s actions are decisive for the success of the measures.

You can do that yourself

The best form of self-help for contact allergies is to identify the allergen and avoid it as much as possible. If the search for the trigger is difficult, an allergy diary can help. In this diary, the person affected records their activities and the observed symptoms. The records have to be kept for several weeks and then often reveal statistical connections between a specific activity and an allergic reaction. These evaluations help the attending physician to narrow down the possible allergen.


Allergic reactions to fragrances and other additives in cosmetic products and household cleaners are widespread. In this case, only care products that are labeled as “hypoallergenic” should be used. There is now a wide range of both care products and decorative cosmetics that have been formulated with the special needs of allergy sufferers in mind. If you are allergic to detergents, it is usually enough to wear gloves when doing housework.

If, due to a contact allergy, there is a risk that the current job can no longer be practiced, it is extremely important that the patient not only seeks medical but also legal advice. A person affected should contact their trade union or a specialist lawyer for social law as soon as possible. In larger cities, charities often offer free legal advice to people in such situations.

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Hello! I am Lisa Newlon, and I am a medical writer and researcher with over 10 years of experience in the healthcare industry. I have a Master’s degree in Medicine, and my deep understanding of medical terminology, practices, and procedures has made me a trusted source of information in the medical world.