Medication rash

definition

A rash caused by medication, e.g. So when a skin reaction to a certain drug substance occurs, it is also called drug eruption (Exanthem = large, uniform rash). This is an allergic reaction that occurs after taking drugs or after applying drugs locally to the skin, the rash being the most common side effect of taking drugs on the skin. The basis for the skin reaction is either a real drug allergy or a pseudo-allergy.

causes

The cause of a rash caused by medication can in principle any medicine However, drug eruptions have frequently been observed in some specific cases. These include in particular various Antibiotics, Painkiller and Anti-seizure remedies (Anti-epileptic drugs).
The basis is one incorrect reaction of the body's immune system to actually non-infectious or dangerous foreign substances with an inflammatory reaction, which in this case manifests itself as a skin rash.

List of medications that commonly cause rash

In principle, any drug can induce a drug eruption. The most common drugs that can cause a drug-induced rash in the context of a drug allergy or pseudo-allergy include the following:

  • Antibiotics: penicillins (see also: rash after penicillin), cephalosporins, sulfonamides
  • Painkillers: Ibuprofen, Diclofenac, Naproxen, ASA
  • Insulins
  • Heparins
  • Thyroid hormones: iodine, thiouracils, perchlorates
  • Anti-epileptic drugs (Anti-seizure remedies) and psychotropic drugs
  • Gout medication: allopurinol
  • Cardiovascular drugs: e.g. ACE inhibitors
  • Vaccines, contrast media, local anesthetics, muscle relaxants (Suxamethonium), Sleeping pills (Barbiturates)

You can find more information on our website Rash after antibiotics.

Concomitant symptoms

Often the extremities or the trunk (Stomach, back, chest) Affecting skin rash consisting of red spots, papules, pustules, vesicles and / or wheals can sometimes be accompanied by diarrhea, nausea, vomiting, feeling sick or cold and fever (see also: Rash with wheals).
More or less severe itching can also occur in the context of the rash. Whether and how pronounced the (accompanying) Symptoms occur varies greatly from person to person.

You might also be interested in the topic: Rash on the upper body

itching

A drug eruption can sometimes result from itching which can be more or less pronounced - individual differences can be determined here. Whether and how severe an itching occurs depends, among other things, on the way in which the rash manifests itself; not every drug eruption manifests itself in the same way.
From small to large blotchy redness and Pustules about the formation of Wheals (Urticaria / hives), the rash can show up in different ways. Wheals, for example, are accompanied by particularly severe itching.

Read our page for more information Itchy rash.

Medication rash on the face

As a rule, the rash occurs due to the intake of medication, especially on the back, stomach and chest area, whereby it then also affects the extremities (arms and legs) can spread.
More rarely, the rash begins on the arms and legs and only then spreads to the trunk of the body.

A drug eruption occurs even more rarely, only or in the facial area; a skin rash that begins here in particular is much more often attributable to viral infections (e.g. Rubella.)

Read more about this under Rash on the face- what is the cause?

diagnosis

If a skin rash appears that is suspected to have occurred due to drug intake, the goal of diagnosis is Finding the triggering drug or active ingredient. This can sometimes be difficult as several medications are often taken at the same time.

If it is a real drug allergy, allergic tests like that can be used Prick test, of the Patch test and Blood tests (IgE determination) help. However, if it is a pseudo-allergy in which it is not the immune system that triggers the allergic reaction, but the active ingredient in the drug itself, these examinations may remain inconclusive.

Treatment / therapy

The first act that should be taken once a drug rash appears - no matter how pronounced the symptoms are - is this immediate discontinuation of the respective drug. Of course, this becomes difficult when several drugs at the same time are taken - then it is the doctor's task to filter out the triggering drug.

The allergic reaction that causes the skin rash can, in turn, be treated with other drugs. Classically, the symptoms are with Glucocorticoids (Cortisone, prednisolone) and Antiallergic drugs (Antihistamines) treated.

If the allergic reaction is particularly pronounced, the rash spreads over the entire body and the reaction becomes systemic, so other symptoms such as fever, Drop in blood pressure, Increase in heart rate and a severe impairment of general well-being should immediately a (intensive) medical treatment is initiated.

Duration of a rash from medication

The rash that usually occurs a few days to two weeks after taking the respective medication (with previous sensitization, even after minutes to hours) usually resolves on its own a few days after stopping the triggering drug without any consequences. Severe courses can sometimes take longer, life-threatening courses such as Stevens-Johnson syndrome or toxic epidermal necrolysis can even end in sepsis due to an infection spreading through the skin.

How do allergies and intolerance differ?

Under one Drug intolerance one understands a (faulty) Reaction of the body's own defense system to ingested or locally applied drugs or their conversion / degradation products. The immune system mistakenly recognizes these as foreign or harmful and begins to fight them, which ultimately turns into a Inflammatory response ends, which can show up in different ways (e.g. in the form of a rash).
It is therefore a special type of allergywhich theoretically can occur in any person at any time in response to any drug.

A so-called must be distinguished from this Pseudo allergy to medication, which is not a classic allergy, which is characterized by a false reaction of the immune system, but a reaction in which certain ingredients of the medication directly specific cells in the body (Mast cells) activate and go to Release of inflammatory substances (histamine) stimulate.