What is the best site for nitroglycerine patch absorption?

AIIMS Rishikesh NO - 2019

Pharmacology

Easy

Appeared in: AIIMS Rishikesh NO - 2019

Explanation

A non-hairy area provides the best surface for patch adhesion, ensuring maximum contact between the drug reservoir and the skin.
Optimal skin contact allows for consistent and predictable absorption of nitroglycerin into the systemic circulation.
Hair can act as a physical barrier, preventing the patch from sticking properly and reducing the surface area available for drug absorption.
The recommended application sites are clean, dry, and hairless areas on the upper body or upper arms.

Option A: This is a common misconception. Nitroglycerin acts systemically on blood vessels throughout the body, not just locally on the heart. Once absorbed, the bloodstream carries it to its site of action.
Option C: This is incorrect because specific site characteristics are crucial. Areas with hair, cuts, scars, calluses, or irritation must be avoided as they can alter absorption rates or cause further skin damage.
Option D: This confuses the transdermal route with the intramuscular (IM) route. Patches deliver medication through the layers of the skin (dermis and epidermis), not into the muscle tissue beneath.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain The core concept is the correct administration technique for transdermal medications, specifically focusing on site selection for a nitroglycerin patch to ensure optimal drug absorption as background academic context rather than a clinical decision trigger.
A key nursing responsibility is patient education on proper patch application, including the importance of site rotation to prevent contact dermatitis and skin breakdown.
Nurses must instruct patients to remove the old patch before applying a new one to prevent accidental overdose from cumulative drug exposure.
What if the patient has a lot of chest hair? The nurse should instruct the patient to clip the hair in the application area. Shaving should be avoided as it can cause micro-abrasions, leading to skin irritation and potentially increased drug absorption.

How to Approach the Question

First, identify the core of the question: it's asking for the 'best site' for a 'nitroglycerine patch'. This points to a question about medication administration technique.
Recall the principles of the transdermal route. The goal is to get the drug through the skin and into the bloodstream consistently.
Analyze the options in light of this principle. What would provide the most consistent absorption?
Option B, 'Non-hairy area,' directly addresses a major physical barrier (hair) to skin contact and adhesion. This makes it a strong candidate.
Evaluate the other options. 'Near the heart' is a common myth for systemic drugs. 'Anywhere on body' is too general and ignores contraindications like irritated skin. 'Muscles' confuses the route of administration.
Conclude that selecting a non-hairy area is the most critical factor among the choices for ensuring effective absorption.

Concept Tested & Keywords

Concept Tested: The core concept is the correct administration technique for transdermal medications, specifically focusing on site selection for a nitroglycerin patch to ensure optimal drug absorption.
Stem keywords: nitroglycerine patch, absorption, best site
Lead-in keywords: What is the best

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