Drug Allergy

"The Clinica has developed the technique of the basophil activation test to analyze in the laboratory possible allergies to drugs and thus correctly evaluate the convenience of carrying out tolerance tests".


How do you know if you have a drug allergy?

Suspected drug allergy is one of the most frequent visits to an allergology specialist.

Drugs are capable of causing adverse reactions of all kinds, not just allergic ones. In addition, the drug is often blamed for a wide range of symptoms, which can be confused with an allergic reaction, but which are caused by a coincident cause.

Allergic reactions to drugs are unpredictable reactions of varying severity, some of which are life-threatening. Any medication can cause allergic reactions.

Among the medicines that most frequently cause allergic reactions are antibiotics, aspirin and other non-steroidal anti-inflammatory drugs (NSAIDs), iodine contrast agents for radiology, anticonvulsants, certain antihypertensives, eye drops and hormones, and even, exceptionally, corticosteroids.

What are the symptoms of drug allergy?

The clinical manifestations that they produce are varied but almost always they are eruptions in the skin, being the most frequent the urticaria (rashes) and the angioedema (swelling of soft parts) in immediate reactions, or the exanthema (rash) in delayed reactions.

These can be life-threatening reactions (anaphylaxis) or severe skin reactions (scalding syndromes and others).

Usually, the symptoms or skin lesions disappear within a few hours after the drug is withdrawn, although, depending on the type of reaction, they may also persist for days or weeks.

The most common symptoms are:

  • Hives
  • Swelling of soft parts (tongue, lips, eyelids...)
  • Rash
  • Itchy skin or eyes

Do you have any of these symptoms?

You may have a drug allergy

How is drug allergy diagnosed?

<p>&nbsp;Pruebas cutaneas</p>

The main problem in the study of drug allergy lies in the lack of reliable diagnostic techniques.

The only definitive test to rule out drug allergy is the provocation or tolerance test, which consists of administering the drug at the usual dose and checking the patient's good tolerance.

The technique of the basophil activation test makes it possible to investigate in the laboratory allergy to a large number of drugs (at least all those that are available in a vial for parenteral administration).

The great advantage it offers is the possibility of detecting in vitro allergies to practically any drug, which makes it a good complement to skin testing. In addition, it is a very useful tool when deciding when to perform a drug tolerance test.

How is drug allergy treated?

Our Immunotherapy Unit is formed by doctors and nurses with great experience in this treatment

The goal of treatment is to relieve symptoms and prevent a serious reaction.

Drug treatment may include antihistamines, bronchodilators, and corticosteroids applied to the skin or given orally or intravenously.

The offending drug and other similar medications should be avoided.

If a medication to which a person is allergic is essential, desensitization or tolerance induction may be performed.

La desensibilización consiste en administrar a un paciente el fármaco al que es alérgico.

Se realiza cuando no existe una alternativa adecuada a ese tratamiento farmacológico. Los casos más frecuentes están relacionados con los antibióticos (en especial penicilinas) y anticancerígenos (sobre todo platinos y taxanos).

En la Clínica Universidad de Navarra tenemos una amplia experiencia en la realización de desensibilizaciones con antibióticos y con fármacos oncológicos.

La realización de una desensibilización es compleja, requiere la coordinación de muchas personas y servicios. No supone que el paciente deje de ser alérgico, si no que "engaña" al sistema inmunológico para que no se desencadene una reacción.

Al inicio de la desensibilización, se administran dosis ínfimas del fármaco, que se van incrementando muy lentamente de forma continua hasta llegar a la dosis completa.

Where do we treat it?


Department of Allergology
of the Clínica Universidad de Navarra

The Department of Allergy and Immunology of the Clinic is part of the Global Allergy and Asthma European Network, composed of the 25 best departments of Allergy in Europe, chosen for their scientific excellence, multidisciplinary work, teaching and international activities.

We have the most advanced diagnostic techniques, we are at the forefront of research and we collaborate with the best experts. We have more than 50 years of experience in the field.

What diseases do we treat?

Imagen de la fachada de consultas de la sede en Pamplona de la Clínica Universidad de Navarra

Why at the Clinica?

  • More than 50 years of experience.
  • Pioneers in the technique of molecular diagnosis by microarray.
  • Nursing specialized in allergic diseases and their care.