Doctors describe a reddening of the skin as a rash (exanthema). It usually occurs in the form of red dots or spots, blisters, wheals or pustules. Rashes appear on the face, neck, armpits, neck, back, chest, under breast, genital area, abdomen, or entire upper body.

They can also cover the hand, upper and lower arm, thigh or the entire leg. A rash can also spread to the mucous membranes.

Skin rashes sometimes even appear from head to toe – i.e. all over the body. Occasionally they may appear with itching; but there are also cases where this accompanying symptom is absent.

There are many causes of a skin rash with or without itching. The most common triggers of skin rash or itchy skin rash include allergies, intolerances, infections and severe mental stress.

The skin reacts with pimples and redness if it does not tolerate a care product – such as a new cream or a new shower gel. The skin sometimes reacts allergically to certain foods, additives or cleaning agents.

A number of medications can cause skin rashes as a side effect or intolerance reaction. Painkillers, antihypertensives and antibiotics in particular carry a certain risk of skin changes.

So after taking antibiotics from the group of penicillins not only increases the risk of subsequent fungal infections, they also cause skin rashes in some people. A rash after taking an antibiotic can look very different. Some sufferers notice small, reddish spots up to large pustules. Others develop fluid-filled blisters.

In most cases, the rashes are harmless. They go away on their own when the affected person stops taking the drug. However, do not discontinue the antibiotic (or the respective drug) on ​​your own, but talk to your doctor about switching to another drug: In many cases, he will give you an alternative that does not irritate the skin.

Vaccinations can also cause skin reactions: a rash is considered a rare vaccine reaction.

A common reason for skin rashes is infection by viruses or bacteria. In children and babies, diseases such as chickenpox, rubella, measles, scarlet fever or three-day fever are possible.

Children’s skin changes differently depending on the disease: Chickenpox, for example, causes red, raised, itchy papules and fluid-filled blisters on the skin. Rubella causes a spotted, reddish rash. With measles and scarlet fever, children get a nodular, patchy rash.

In adults, viral infections such as herpes zoster (shingles) or glandular fever, or bacteria such as the causative agent of syphilis are possible causes of a skin rash.

In the case of infections in particular, those affected can get the rash after fever. In the case of three-day fever, for example, patchy skin changes on the upper body only appear after a few days. Patients with measles, rubella and scarlet fever also initially have a fever that subsides after a few days. The skin then reacts with the characteristic rash.

Infections with the corona virus may also lead to skin reactions: in some cases, doctors observe a skin rash with an infection with the omicron variant.

Rashes can be made worse by stress, anxiety, or depression. In particular, diseases such as neurodermatitis, psoriasis, acne, herpes and hives have a strong psychological component. It has not yet been scientifically clarified whether mental problems are the cause or the consequence of the skin diseases.

An increased body core temperature can also be a reason for a skin rash with itching, redness or wheals. Doctors then speak of sweating urticaria. This is a form of hives. About every tenth adult suffers from it – for example in summer when it is hot, after sport, after showering or even after spicy food. The rash usually goes away when the body temperature goes down.

Another trigger for skin rashes are parasites such as mites or head and clothes lice. When the rash is caused by mites, doctors call it scabies. It causes severe itching.

However, the disease occurs very rarely. Only those who have a weak immune system and live under poor hygiene conditions have an increased risk of getting scabies.

Some women get a skin rash during pregnancy. Experts speak of an atopic pregnancy dermatosis. The skin changes often begin in early pregnancy within the first three months.

Those affected usually feel a very itchy rash on the face, neck, décolleté and on the bends of the arms and legs. There is no risk for the unborn child.

Dry skin is very sensitive. It often feels uncomfortable, itchy and tense. In addition, it is irritated more quickly and also becomes inflamed more quickly.

This is why people with dry skin are more likely to get rashes. Depending on what triggers the rash and what its characteristics are, it can also be caused by a skin disease, such as neurodermatitis.

A sudden rash can also occur with human immunodeficiency virus (HIV) infection.

About two to four weeks after infection with HIV, the body often reacts with flu-like symptoms. In addition to fever, night sweats and swelling of the lymph nodes, those affected usually get a red, blotchy and itchy rash.

In the case of an infection with HIV, the rash occurs mainly on the face and upper body, more rarely on the arms and legs.

If you suspect that you have contracted HIV, get an HIV test. In this way, you can receive the right treatment at an early stage and prevent AIDS.

Alcohol or chronic alcoholism can not only damage the liver, but also lead to skin changes – such as redness, skin rash, psoriasis or pimples.

No matter how itchy your skin is, you should definitely avoid scratching the affected areas. Scratching areas of skin can cause the rash to get worse, last longer, or leave scars.

In many cases, a rash is harmless and you can treat it yourself. If your skin is irritated by a new piece of clothing or a new cream, it is enough to change the product.

We recommend pH-neutral care products without artificial additives. Wear loose-fitting cotton clothing to avoid rubbing and irritation.

To relieve the itching, you can cool the affected areas. Soothing creams and ointments can also help. Chamomile, for example, is a very popular home remedy. In the form of tea or ointment, the plant helps to soothe the skin.

Calendula as a cream or ointment also soothes the skin and reduces severe swelling. Aloe Vera reduces itching as a gel or cream.

However, if the skin rash is severe or if there are other symptoms, it is advisable not to continue self-medication. A doctor can determine the cause of the rash and initiate targeted treatment.

Those affected should also make sure that their skin does not become too dry. It is advisable to be outside in the fresh air often, but to protect the skin from intense solar radiation or severe cold.

Keep irritants and pollutants away from your skin. Use non-latex protective gloves when handling aggressive substances.

If skin rashes occur in children or babies, parents should take them to the pediatrician.

If the rash appears after an insect bite, observe your body more closely. It is often sufficient if you cool the affected area and apply a decongestant ointment.

If severe allergic reactions occur, consult a doctor. In case of severe reactions, you should even call the emergency services (112).

Also consult a doctor in the following cases:

The family doctor or pediatrician can determine whether an allergy or an infectious disease is present. Depending on the illness, he will treat you himself or he will refer you to a dermatologist.

All about our largest organ

This article was written by Katrin Ewert, medical journalist

The original of this post “Itching, redness or wheals: when you should go to the doctor for a skin rash” comes from FOCUS doctor search.