Penicillin allergy

Penicillin allergy

overview

Penicillin allergy is an abnormal reaction of your immune system to the antibiotic penicillin. Penicillin is prescribed to treat various bacterial infections.

Common signs and symptoms of penicillin allergy include hives, rash, and itching. Severe reactions include anaphylaxis, a life-threatening condition that affects multiple body systems.

Research has shown that penicillin allergies may be over-reported - a problem that can lead to the use of less appropriate and more expensive antibiotic treatments. Therefore, an accurate diagnosis is necessary when penicillin allergy is suspected to ensure the best treatment options in the future.

Other antibiotics, especially those with chemical properties similar to penicillin, can also cause allergic reactions.

Symptoms

Drug rash

Drug rash

A drug rash usually begins within two weeks of taking a new medication and begins as discrete red spots that spread and cover large areas of the body.

Signs and symptoms of penicillin allergy often appear within an hour of taking the drug. Less commonly, reactions can occur hours, days or weeks later.

Signs and symptoms of penicillin allergy may include:

• Hautausschlag
• Nesselsucht
• Juckreiz
• Fieber
• Schwellung
• Kurzatmigkeit
• Keuchen
• Laufende Nase
• Juckende wässrige Augen
• Anaphylaxie

Anaphylaxis

Anaphylaxis is a rare, life-threatening allergic reaction that causes widespread dysfunction of body systems. Signs and symptoms of anaphylaxis include:

• Verengung der Atemwege und des Rachens, was zu Atembeschwerden führt
• Übelkeit oder Bauchkrämpfe
• Erbrechen oder Durchfall
• Schwindel oder Benommenheit
• Schwacher, schneller Puls
• Abfall des Blutdrucks
• Krampfanfälle
• Bewusstseinsverlust

Delayed reactions due to penicillin allergy

Less common allergic reactions to penicillin occur days or weeks after exposure to the drug and may last for some time after you stop taking it. These conditions include:

• Serumkrankheit, die Fieber, Gelenkschmerzen, Hautausschlag, Schwellungen und Übelkeit verursachen können
• Arzneimittelinduzierte Anämie, eine Verringerung der roten Blutkörperchen, was zu Müdigkeit, unregelmäßigem Herzschlag, Kurzatmigkeit und anderen Anzeichen und Symptomen führen kann
• Arzneimittelreaktion mit Eosinophilie und systemischen Symptomen (DRESS), was zu Hautausschlag, hoher Anzahl weißer Blutkörperchen, allgemeiner Schwellung, geschwollenen Lymphknoten und dem Wiederauftreten einer ruhenden Hepatitis-Infektion führt
• Stevens-Johnson-Syndrom oder toxische epidermale Nekrolyse, was zu starker Blasenbildung und Abschälen der Haut führt
• Entzündung der Nieren (Nephritis), was zu Fieber, Blut im Urin, allgemeiner Schwellung, Verwirrtheit und anderen Anzeichen und Symptomen führen kann

Side effects that are not allergic reactions

Penicillin side effects can occur - as with other medications - that are not an allergic reaction to the medication. Depending on the type of penicillin, common side effects may include mild nausea or diarrhea, headache, or vaginal itching. Signs or symptoms of an infection you are being treated for - or unrelated symptoms - may also be misinterpreted as an allergic drug reaction.

When to go to the doctor?

See your doctor as soon as possible if you notice any signs or symptoms of a penicillin allergy. It is important to understand and discuss what an allergic reaction is, what a typical side effect is, and what you can tolerate when taking a medication.

Call 911 or emergency medical help if you notice signs of a serious reaction or suspected anaphylaxis after taking penicillin.

Causes

A penicillin allergy occurs when your immune system becomes hypersensitive to the drug - mistakenly reacting to the drug as a harmful substance, as if it were a viral or bacterial infection.

Before the immune system can become sensitive to penicillin, you must be exposed to the drug at least once. When your immune system misidentifies penicillin as a harmful substance, it develops an antibody against the drug.

The next time you take the drug, these specific antibodies will flag it and direct immune system attacks on the substance. Chemicals released by this activity cause the signs and symptoms associated with an allergic reaction.

Previous exposure to penicillin may not be obvious. Some evidence suggests that trace amounts of it in the food supply may be enough for a person's immune system to form an antibody against it.

Penicillins and related drugs

Penicillins belong to a class of antibacterial drugs called beta-lactam antibiotics. Although the drugs' mechanisms vary, they generally fight infections by attacking the walls of bacterial cells. In addition to penicillins, other beta-lactams that are more commonly associated with allergic reactions include a group called cephalosporins.

If you have had an allergic reaction to one type of penicillin, you may or may not be allergic to other types of penicillin or to some cephalosporins.

Penicillins include:

• Amoxicillin
• Ampicillin
• Dicloxacillin
• Nafcillin
• Oxacillin
• Penicillin G
• Penicillin v
• Piperacillin
• Ticarcillin

Cephalosporins include:

• Cefaclor
• Cefadroxil
• Cefazolin
• Cefdinir
• Cefepim (Maxipin)
• Cefotetan
• Cefprozil
• Cefuroxim
• Cephalexin (Keflex)

Risk factors

While anyone can have an allergic reaction to penicillin, some factors can increase your risk. These include:

• Eine Geschichte von anderen Allergien, wie Nahrungsmittelallergie oder Heuschnupfen
• Allergische Reaktion auf ein anderes Medikament
• Eine Familiengeschichte der Arzneimittelallergie
• Erhöhte Exposition gegenüber Penicillin aufgrund hoher Dosen, wiederholter Anwendung oder längerer Anwendung
• Bestimmte Krankheiten, die häufig mit allergischen Arzneimittelreaktionen einhergehen, wie z. B. eine Infektion mit HIV oder dem Epstein-Barr-Virus

prevention

If you have a penicillin allergy, the easiest prevention is to avoid the drug. Measures you can take to protect yourself include the following:

• Gesundheitspersonal informieren. Stellen Sie sicher, dass Ihre Penicillinallergie oder andere Antibiotikaallergie in Ihren medizinischen Unterlagen eindeutig identifiziert ist. Informieren Sie andere Angehörige der Gesundheitsberufe, wie z. B. Ihren Zahnarzt oder Facharzt.
• Trage ein Armband. Tragen Sie ein medizinisches Alarmarmband, das Ihre Arzneimittelallergie identifiziert. Diese Informationen können im Notfall die richtige Behandlung sicherstellen.

Sources:

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