Drug Allergy Testing
View All TestsWhat Is Drug Allergy?
Drug allergy is an adverse immune-mediated reaction to a medication. It is different from drug side effects or intolerance. True drug allergy involves the immune system and can present as urticaria, angioedema, skin rashes, or in severe cases, anaphylaxis.
The most commonly reported drug allergies include penicillin and other beta-lactam antibiotics, NSAIDs (e.g., ibuprofen), and anaesthetics. However, studies have shown that up to 90% of people labelled as "penicillin allergic" are not truly allergic when formally tested.
Important: Drug allergy testing is complex and often requires specialist assessment beyond blood tests alone. IgE blood testing can be informative for some drug allergies, but a negative result does not rule out allergy. We recommend discussing drug allergy concerns with your GP or an allergist who may arrange skin testing or drug provocation under medical supervision.
How Testing Works
Choose Your Test
Select from our range of allergy blood tests and book a convenient time at our South Kensington clinic. No GP referral needed.
Nurse Blood Draw
A qualified nurse takes a small blood sample at our clinic. The appointment is quick and straightforward.
Get Your Results
Results are sent directly to you, typically within a few working days. Share them with your GP or specialist to guide your next steps.
Available Tests
Note: Drug allergy investigation often requires specialist assessment beyond blood tests alone. View all tests or consult your GP for referral.
Why Choose a Diagnostic-Only Clinic?
Unlike clinics that provide both testing and treatment, our nurse-led service focuses solely on accurate diagnostic testing. Because we don't offer treatments or prescriptions, there is no commercial incentive to recommend unnecessary tests — just honest, impartial results you can trust.
Nurse-Led & Impartial
Our qualified nurses collect your sample — we don't prescribe, treat, or have any reason to upsell.
Results You Own
Your results are sent directly to you. Take them to your GP or a specialist to discuss what's best for your situation.
You Stay in Control
Understand your allergy profile, then decide with your healthcare professional what steps to take next.
Related Reading
Frequently Asked Questions
Can a blood test confirm penicillin allergy?
Specific IgE blood tests for penicillin exist but have limited sensitivity. A negative blood test does not rule out penicillin allergy. Formal assessment typically requires skin testing and/or supervised drug provocation at a specialist allergy clinic.
Why is it important to clarify a drug allergy label?
An incorrect "penicillin allergy" label can result in the use of broader-spectrum antibiotics, which may be less effective, more expensive, and contribute to antimicrobial resistance. De-labelling through formal testing is an important public health initiative.
Do I need a GP referral for allergy testing?
No. You can book directly with our clinic without a GP referral. Simply choose your test and select a convenient appointment time. If you're unsure which test is right for your symptoms, our team can help guide your selection.
Do I need to stop taking antihistamines before a blood test?
No. Unlike skin prick testing, IgE blood tests are not affected by antihistamines or other allergy medications. You can continue taking your regular medications before your appointment.
What should I do with my results?
As a diagnostic-only clinic, we provide results directly to you. For suspected drug allergy, we strongly recommend GP or specialist interpretation. Formal drug allergy assessment may require supervised drug challenge testing.
Start Investigating Drug Allergy
Book a blood test at our South Kensington clinic
Browse All Tests