14, June 2024
09:00 – 10:00

Drug hypersensitivity reactions

Dr. Krasimira Baynova

Allergist and national consultant for Spain on hereditary angioedema

Virgen del Rocio University Hospital, Seville, Spain

 

An adverse drug reaction/ADR/ is any unintended, harmful effect of a drug that occurs at doses used for prophylaxis, diagnosis or treatment in humans and affects 1/10 of the general population. Only 10% of these reactions are due to true hypersensitivity. Hypersensitivity reactions are ADRs caused by active ingredients and/or excipients that manifest clinically with signs and symptoms that differ from the pharmacological effects of the drug. Hypersensitivity reactions are allergic and non-allergic. Allergic reactions, according to their immunological mechanism, are of 4 types: type 1- IgE mediated; type 2 – IgG or IgM mediated cytolysis; type 3- mediated by immune complexes and type 4 – cell mediated.

Allergy testing for a given drug is performed exclusively  in case of a previous reaction with this drug or with a structurally similar substance. Allergy tests have no positive predictive value in individuals who have not had a previous reaction to the suspected drug.

To diagnose an allergic reaction to a drug, in vitro tests/ non-specific blood tests, tryptase, specific IgE, basophil activation test, test with transformation/ activation of lymphocytes/ and in vivo tests (skin testing, challenge test with controlled exposure to the drug) are used. The sensitivity and specificity of the all those tests depends on the type of drug being tested and the type of allergic reaction the patient has had.

A negative skin test does not rule out an allergic reaction. The challenge test with controlled exposure to the full therapeutic dose of the medication is the gold standard for ruling out an allergic reaction and should be used to confirm negative skin test results with antibiotics, NSAIDs, local anesthetics, and latex.

 

 

Key knowledge/skills that the lecture will provide to attendees

 

– update in the classification of drug hypersensitivity reactions

– treatment of an acute systemic allergic reaction/ anaphylaxis/

– correct clinical indication for referral to an allergist when suspected

allergic reaction to drugs

-differential diagnosis of drug hypersensitivity reactions

– update in the rules of good clinical practice

Ticket to 21.05.2024

200

BGN

Ticket after 23.05.2023

250

BGN

Cover for gala dinner

90

BGN