AIIMS Jodhpur SNO-2023: The first drug of choice to treat an anaphylactic reaction is:

AIIMS Jodhpur SNO-2023

Pharmacology

Easy

Appeared in: AIIMS Jodhpur SNO-2023

Explanation

Epinephrine is the essential, first-line medication for treating anaphylaxis due to its rapid and life-saving effects.
It acts on alpha-adrenergic receptors to cause vasoconstriction, which reverses hypotension and reduces angioedema.
Simultaneously, its action on beta-adrenergic receptors leads to bronchodilation (opening airways), increased heart rate and contractility, and suppression of further mediator release from mast cells.

Option A: Corticosteroids have a slow onset of action (hours) and are not effective for treating the immediate, life-threatening symptoms of anaphylaxis.
Option C: Antihistamines primarily relieve cutaneous symptoms like hives and itching but have minimal effect on life-threatening respiratory distress or hypotension.
Option D: Bronchodilators only address bronchospasm and do not treat the systemic effects of anaphylaxis like shock and angioedema.

Visual 1: Flowchart: Step-by-step emergency management of anaphylaxis, highlighting the immediate administration of epinephrine.
Visual 2: Diagram: Illustration of epinephrine's mechanism of action on alpha-1, beta-1, and beta-2 receptors during anaphylaxis.

Clinical Relevance

Nursing practice connection: Knowing First-line treatment for anaphylaxis helps nurses interpret findings accurately and avoid errors in routine assessment, medication administration, and patient teaching.
Immediate recognition of anaphylaxis and prompt administration of intramuscular epinephrine are critical nursing responsibilities that directly impact patient survival.
Nurses play a key role in educating patients with known severe allergies and their families on how to use an epinephrine auto-injector (e.g., EpiPen) and the importance of seeking emergency care after use.
What if the patient is taking a beta-blocker and has a poor response to epinephrine? The nurse should anticipate the potential need for glucagon, which can increase heart rate and contractility through a non-adrenergic pathway.

How to Approach the Question

First, identify the core of the question: it asks for the 'first drug of choice' for a specific medical emergency.
Recognize the condition as anaphylaxis, a severe, life-threatening allergic reaction.
Recall the standard treatment protocol for anaphylaxis. The key is to differentiate the immediate, life-saving intervention from adjunctive or secondary treatments.
Evaluate the options based on their mechanism and speed of action. Epinephrine acts rapidly to reverse all major life-threatening features of anaphylaxis (hypotension, bronchoconstriction, angioedema).
Eliminate the other options by identifying their roles as secondary or supportive treatments (corticosteroids for late-phase reaction, antihistamines for skin symptoms, bronchodilators for persistent wheezing).

Concept Tested & Keywords

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KD Tripathi - Essentials of Medical Pharmacology (6th Edition) p. 389-398