Causes by body region

One of the most common causes of facial rashes is an allergic reaction of the skin to substances contained, for example, in facial care products, powders or cosmetics. (see: allergic rash) This allergic reaction leads to an excessive activation of the immune system, as a result of which increased messenger substances (mediators) are released from the cells. These messenger substances cause reactions in the blood vessels of the skin, which are similar to inflammations.

Among other things, the blood supply to the vessels is increased, leading to redness and swelling, which is then perceived as a rash on the face. This allergic-inflammatory reaction is also the cause of eczema and so-called contact dermatitis, both of which can lead to rashes on the face after contact of the skin with allergenic substances. Excessive skin care can also lead to a rash on the face.

The misunderstood “care” dries out the skin or becomes irritated by mechanical irritation, such as when shaving or even peeling. If the skin can no longer maintain its natural protective barrier as a result, this often leads to rashes because bacteria, viruses and fungi have an easier time penetrating the skin.Another common cause of facial rash is acne. It occurs mainly during puberty due to the altered hormone balance and leads to a disturbance of the sebaceous glands, which become inflamed and are ultimately the cause of pimples and skin rashes.

Other skin diseases such as neurodermatitis on the face or psoriasis also lead to a rash on the face. In very hot weather, for example during a vacation in the tropics, heat spots (miliaria) are often the cause of a rash on the face. Heat spots are caused by blockage of the ducts of sweat glands, which prevents the sweat produced from reaching the surface of the face.

This promotes bacterial colonization of the glands, which can lead to an inflammatory reaction and thus to a rash. A rash on the face can also be caused by stress (see: Skin rash due to stress) and is therefore a physical manifestation of psychological stress. In rare cases, autoimmune diseases or skin cancer can also become conspicuous as a rash.

The causes of skin rash on the neck are very similar to those on the face. For example, allergies to certain foods, drugs or skin care products often lead to a rash on the neck. Another cause of a rash on the neck is acne, which is mainly found on the face, but can also spread to the neck and lead to a rash there.

Furthermore, infections caused by viruses and bacteria can lead to a rash on the neck. These can be exogenous, i.e. caused by external colonization of the skin with bacteria or viruses, and can lead to an isolated rash on the neck. On the other hand, systemic infectious diseases often affect the skin and thus the skin on the neck.

This is the case with chickenpox or rubella, for example. Allergic reactions are often responsible for a rash on the chest. In most cases, a reddish, itchy rash on the chest area suddenly appears.

The skin in this area can become very flaky and can also be very painful. Sometimes there can also be a fungal infection on the chest. Especially in places where skin lies on skin, there is usually a warm and humid environment, which can promote a fungal infection.

If there is any doubt, a skin smear can provide evidence of a fungal infection of the skin. Afterwards, so-called antimycotic ointments or creams are used. Healing should take place within a week.

Other causes of a skin rash on the breast can generally be allergic skin reactions to a certain lotion or detergent that has recently been used. If itching occurs after changing the product, the product should be changed again. In addition, care products that keep the skin moist and supple can be used.

Frequent washing of the skin can also lead to a rash in the breast area. This is because the acid mantle of the skin has been attacked. Reducing the frequency of washing usually also leads to a restoration of the acid mantle, which is very important for the defence against infections.

As a rule, the forearms are affected by skin rashes. More rarely, a skin rash or pus pimples on the shoulder and upper arms may occur. The reasons why a rash can occur in the area of the arms are manifold.

Often it is a non-specific allergic reaction to a certain substance that leads to an itchy and agonizing rash and reddening of the skin. An allergy test can provide initial indications of the substance causing the allergy. Recently changed shower gels or shampoos can be the trigger of a rash and should be changed.

Relatively often a rash on the arms is triggered by neurodermatitis. Neurodermatitis is a skin reaction caused by an overactive immune system. Often at the bends of the arms, there are almost always itchy, reddish skin symptoms, which can also become stronger and more tormenting when warm or when sweating.

Treatment with cortisone in the form of an ointment is usually successful, but must be repeated in the event of a new episode of neurodermatitis. The skin disease is hereditary. If there have already been cases of neurodermatitis in the family, the risk of recurrence increases.

A skin rash on the abdomen can have different causes. In addition to an allergy-related cause, neurodermatitis can also lead to a skin rash in the abdomen area.Often the crook of the arm is also affected by the rash. Typical for neurodermatitis would be an itchy, reddish scaly rash in the area of the abdomen.

A neurodermatitis runs in thrusts and is usually accelerated by a warm and humid millieu. Thus, in warm periods, when the body sweats, the development of neurodermatitis is intensified. The shingles, which can occur very often in the area of the abdomen, is to be distinguished from neurodermatitis.

In most cases, shingles begins with small, isolated standing vesicles, which then burst open and release a clear fluid. At this time, the patient is highly infectious. A short time later, the blisters dry out again, and further on, the grind falls off.

Despite the obvious healing of the rash caused by shingles, pain in the area of the skin may continue for a long time afterwards. These symptoms can sometimes last for weeks to months of rare years and require intensive medical treatment with a drug used for nerve pain. Among the allergenic substances that lead to a skin rash in the abdominal area, there can always be certain metals.

These come into contact with the skin, for example through belt buckles. The skin reactions in the abdominal area triggered by belts almost always occur close to the navel. An isolated skin rash on the back is relatively rare.

It can manifest itself for example in the form of red spots on the back. Often, however, the back is the place where a rash begins and then spreads to other parts of the body. This is the case, for example, with so-called three-day fever (exanthema subitum) or typhoid fever.

Shingles also develops a skin rash on the back. Here, varicella zoster viruses, which caused chickenpox in childhood, spread along nerve tracts in the back. Since the nerves in the back are arranged in segments, the skin rashes caused by shingles impress with their usually sharply defined, belt-shaped appearance, which gives them their name.

Frequently, drug exanthema, i.e. rashes due to intolerance to drugs, also start in the back. Acne is a further cause of a rash on the back. It occurs on the back, but also on the face, neck and chest.

Small reddish pustules that spread over the body, back, chest and face should always remind you of a childhood disease such as chickenpox. Measles appear as large reddish spots also on the trunk and are usually associated with high fever and severe malaise. Other childhood diseases that cause a rash all over the body can be rubella or scarlet fever.

Sharply defined, reddish areas can always be caused by shingles. Here, itching, dry, reddish pustules appear at first, which then burst open and empty out in liquid form. Non-specific irritations of the skin, such as those caused by too frequent washing or too dry skin, can also lead to a rash on the body.

In most cases, however, only a part of the body is affected by the rash and rarely the entire body. Before treating a rash, the diagnosis should be established or at least narrowed down considerably. Furthermore, there are internal diseases, i.e. diseases of certain organs, which cause a rash of the whole body. This is the case with certain kidney diseases, for example.