Penicillin Antibiotic Allergy Screen

Testing for Allergies:

Amoxicillin, Amoxicillin/Clavulanic acid, Benzylpenicillin, Cefuroxime, Clavulanic acid, Phenoxymethylpenicillinkalium



A penicillin allergy can trigger mild symptoms such as itching and nausea, severe anaphylaxis, kidney inflammation, anaemia and more.


What is a penicillin allergy?

Your body mistakenly treats penicillin as a threat and releases antibodies to fight that threat. This is what causes the reaction.

What are the symptoms?

Typical symptoms range from sneezing, itching and watering eyes to facial swelling, hives and, in worst cases, anaphylaxis. Can also lead to kidney inflammation, anaemia and serum sickness.

Does a penicillin allergy mean I am allergic to all antibiotics?

No. There are a range of antibiotic categories. It is possible you may only be allergic to penicillin.

How do I know if I have an allergy?

A simple blood test is all you need. Book yours now.

Did You Know?

Severe anaphylactic reactions to penicillin are rare (with just 1-5 cases for every 10,000 users). But hypersensitivity (less severe allergy) is very common.

What is a penicillin allergy?

A penicillin allergy develops when your body mistakenly treats the penicillin within your system as a threat. It develops antibodies to fight this threat, and next time you take penicillin the release of these antibodies will trigger an allergic reaction.

Having a penicillin allergy does not mean that you are allergic to all antibiotics, although you may be allergic to more than one. You can check for a wider range of antibiotic allergies here.

Do you still have a penicillin allergy?

If you believe you have a penicillin allergy, it is important to test periodically to ensure that is still the case, especially if you have not been tested for some years. That is because:

  • It is not uncommon for penicillin allergies to subside over time which could mean you that you are needlessly avoiding penicillin and instead taking other antibiotics less suited to your condition; and
  • If you have suffered an allergic reaction to penicillin in the past, you could suffer a more severe reaction in the future if you still have the allergy and take penicillin again.

What are the symptoms of a penicillin allergy?

It is important to distinguish an allergic reaction to penicillin (which can be life threatening) from a side effect to taking penicillin (which can be unpleasant, but rarely serious). Side effects tend to result in digestive problems (cramps, nausea, vomiting). Allergies can trigger nausea and vomiting too, but may also include:

  • Itchy mouth, throat and ears
  • Persistent coughing
  • A raised, red, itchy rash anywhere on the body (hives)
  • Swelling around the face, particularly the eyes, lips, tongue and roof of the mouth
  • Fever

The most severe reaction to a penicillin allergy, anaphylaxis, can be life threatening. If you experience shortness of breath, feel faint and have clammy skin and a racing heartbeat, dial 999.

Most allergies become apparent within an hour of taking penicillin, although some take longer to appear. The following can take days to become noticeable, but can all be symptoms of penicillin allergy:

  • Anaemia symptoms include fatigue and shortness of breath
  • Nephritis (inflamed kidneys) symptoms include fever, confusion, blood in urine
  • Serum sickness symptoms include rash, joint pain, fever and nausea

How do I get tested?

Better2Know offers a simple blood test designed to check for penicillin allergy. The test covers:

  • Amoxicillin
  • Amoxicillin/Clavulanic acid
  • Benzylpenicillin
  • Cefuroxime
  • Clavulanic acid
  • Phenoxymethylpenicillinkalium

To book your test, call the Better2Know team on the number provided on this page.