What is Penicillin allergy?

What is Penicillin allergy?

5 Jan 2023
Stefano Mirabello
Stefano Mirabello
Medical Writer

If you’ve ever heard of an allergic reaction to penicillin and felt curious or concerned, you’re not alone many people have questions about this drug allergy. A penicillin allergy may feel confusing and overwhelming, but understanding its basics can be empowering. In this blog post, we’ll break down the facts so that you are informed and prepared if a diagnosis of a penicillin allergy is on your horizon. We’ll provide insights into what it means to have this type of allergy, as well as tips for managing it in the most effective way possible. Read on for more information about penicillin allergies.

What is the purpose of penicillin?

Penicillin is part of a larger drug class called beta-lactam antibiotics, which include the common penicillins and cephalosporins. It was discovered by Alexander Fleming in 1928 and has since been used to treat and prevent a variety of bacterial infections. Penicillin works by targeting the cell wall of bacteria and inhibiting their growth. This helps the body clear out infection-causing bacteria and reduces the risk of further infections. It is typically taken orally in tablet form, but can also be administered intravenously. It is used to treat diseases such as strep throat, pneumonia, meningitis, and other serious illnesses.

What causes a penicillin allergy?

Penicillin allergy occurs when your body’s immune system overreacts to the drug and produces antibodies called immunoglobulin E (IgE). IgE antibodies attach themselves to cells that release histamines, which are responsible for the signs and symptoms of an allergic reaction. Most often, this happens because your body’s immune system mistakes penicillin for a harmful substance, such as bacteria or virus, and mounts an attack against it. In some cases, however, a person may develop an allergy without having any prior exposure to penicillin.

Signs & symptoms of penicillin allergy

The signs and symptoms of a penicillin allergy vary from person to person, ranging from mild to severe reactions. Penicillin allergy is a serious condition, but fortunately, it is one that can be managed with the support of proper diagnosis and medical care. Some common signs and symptoms of penicillin allergy may include:

  • Hives
  • Skin reaction, redness, or rashes
  • Swelling of the throat or tongue
  • Wheezy airways or shortness of breath or trouble breathing
  • Stomach pain
  • Nausea
  • Vomiting
  • Itching

More severe reactions include:

  • Anaphylaxis. A life-threatening reaction that can cause difficulty breathing, chest tightness, dizziness and loss of consciousness. It requires an immediate epinephrine injection as well as hospital care to maintain blood pressure and support breathing

If you experience any of these symptoms after taking penicillin medication, seek medication attention right away to make sure it’s safe for you to continue with the medication or if further tests or treatments may be needed. Working together with your medical provider can help ensure that you stay safe while still being able to get the treatment you need.


Treating penicillin allergies

One of the first steps is to undergo a skin test, where a small dose of the antibiotic is injected under the skin. This is called a penicillin skin test. This test will let the allergist know how severe your allergy symptoms will be upon taking penicillin and if treatment should move forward.

If skin testing shows you are mildly or moderately allergic to penicillin, your doctor may suggest that you go through desensitization. This process will slowly reintroduce small doses of penicillin into your system and over time increase the dosage until it reaches the therapeutic level your body needs. For those with very severe reactions, you may be given a corticosteroid or antihistamines for mild reactions in addition to skin testing before attempting desensitization.

Treating penicillin allergies is not always simple but with proper steps taken by an allergist, it can safely be done, reducing discomfort and making sure patients receive needed treatment for any infection.

What should you avoid if you are allergic to penicillin?

If you have an allergy to penicillin, it is important to be proactive about identifying and avoiding products that contain the antibiotic. Medication containing penicillin should be avoided, as well as antibiotics derived from the same fungus family such as amoxicillin, dicloxacillin, ampicillin, nafcillin, oxacillin, flucloxacillin, carbenicillin, ticarcillin and piperacillin. Further, infections known to be treated with these medications such as strep throat and ear infections should be treated with alternative antibiotics that do not contain penicillin components. It is essential that you read the labels on medications to ensure that any product that you’re taking does not contain the medication.

Additionally, it is imperative to speak with your doctor or pharmacist; they should be able to provide you with a comprehensive list of alternative treatment options if your prescription includes penicillin. Lastly, it also may be beneficial to inform family members and peers of your allergies if they are in charge of picking up medications for you or providing treatments. Taking these steps will help ensure your safety and prevent potential reactions.

What foods contain penicillin?

If you have an allergy to penicillin, be mindful of the foods that you consume. Generally, penicillin is not present in food naturally, but there are a few products that may contain penicillin in trace amounts due to the manufacturing process. These typically include cheese, fruits and vegetables, processed grains and various condiments like ketchup or soy sauce. When shopping for penicillin-free food items and deciding what to add to your grocery list, look for cheeses made with vegetable rennet, unprocessed flour, as well as sugar and spices prepared without preservatives. Additionally, antibiotics aren’t used during animal rearing for products such as seafood and egg production. Taking these steps can help you reduce any potential exposure to penicillin within your diet!

What is the difference between an allergy and the side effects of penicillin?

Allergies and side effects from taking penicillin are two very different things. An allergy is an immediate reaction that occurs after exposure to an allergen, such as penicillin. Those who have a penicillin allergy will often show symptoms like swelling, hives, skin rashes, difficulty breathing or chest tightness shortly after exposure. In contrast, side effects of taking penicillin are a reaction to the medication itself and usually happen after several doses. However, they may also be experienced immediately upon exposure but often do not manifest until days after taking the medication. Side effects tend to be mild and include nausea, vomiting and diarrhoea; although in rare cases they can be more serious. Penicillin taken by those who have an allergy may cause a much worse reaction than it would in those without an allergy, so it’s important to communicate any allergies or reactions you’ve had with medications to your healthcare provider.

Understanding why you have a penicillin allergy is important for the safe management of your condition. A good place to start is by talking with your healthcare professional about any questions or concerns you have about this type of medication sensitivity so that they can provide proper guidance on how best to protect yourself should you ever need antibiotics again for future illnesses or infections. By being informed about what causes and how best to treat this type of allergy, you can greatly reduce your risk for future adverse reactions associated with taking antibiotics containing penicillin drugs – giving yourself peace of mind that you don’t have anything additional to worry about during recovery!

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