Patient is allergic to Beta-lactamase and which of following drug is safe to administer?

AIIMS Delhi NO- 2019

Pharmacology

Medium

Appeared in: AIIMS Delhi NO- 2019

Explanation

Vancomycin is a glycopeptide antibiotic, which is structurally different from beta-lactam antibiotics.
It does not contain the beta-lactam chemical ring that is responsible for triggering allergic reactions in susceptible individuals.
Due to its different mechanism of action and structure, it is considered a safe alternative for patients with a documented allergy to beta-lactam drugs like penicillin and cephalosporins.

Option A: Amoxicillin is an aminopenicillin, which is a type of beta-lactam antibiotic. Administering it to a patient with a known beta-lactam allergy is contraindicated and could cause a severe allergic reaction.
Option B: Penicillin is the original and prototype beta-lactam antibiotic. Giving it to a patient with a known allergy to this class would directly expose them to the allergen, risking anaphylaxis.
Option D: Cefazoline is a first-generation cephalosporin. Cephalosporins are a major class of beta-lactam antibiotics. There is a known risk of allergic cross-reactivity between penicillins and cephalosporins, especially first-generation agents.

Clinical Relevance

Nursing practice connection: Use the key finding related to Antibiotic Classes and Drug Hypersensitivity to guide bedside assessment, documentation, and the next nursing action.
A core nursing responsibility is to 'do no harm'. Verifying patient allergies before administering any medication is a critical patient safety check to prevent potentially life-threatening allergic reactions.
Understanding antibiotic classes and the potential for cross-reactivity is essential for safe medication administration. An allergy to one beta-lactam (e.g., penicillin) should be considered a potential allergy to all beta-lactams until proven otherwise.
What if? If a patient reports a mild, non-itchy rash to amoxicillin as a child, the provider might consider a 'graded challenge' with a cephalosporin in a controlled setting. However, for a history of severe reaction (e.g., anaphylaxis, hives, swelling), all beta-lactams are strictly avoided, and a non-beta-lactam like vancomycin or a macrolide is chosen.

How to Approach the Question

First, identify the key information in the question: the patient has a 'Beta-lactam' allergy and you need to find a 'safe' drug.
Recognize that 'Beta-lactamase allergy' is a common misstatement for an allergy to the beta-lactam antibiotic class.
Review each option and classify it based on its antibiotic family.
Categorize Amoxicillin and Penicillin as 'Penicillins' (a beta-lactam subclass).
Categorize Cefazoline as a 'Cephalosporin' (another beta-lactam subclass).
Identify Vancomycin as a 'Glycopeptide', which is not a beta-lactam.

Concept Tested & Keywords

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E6 Nelson Textbook of Pediatrics(2024) — Volume 1 p. 1471-1473