Which of the following drugs used in the treatment of pulmonary hypertension is a prostacyclin receptor agoni… - INI-CET EXAM -2025

INI-CET EXAM -2025

Pharmacology

Easy

Appeared in: INI-CET EXAM -2025

Explanation

Selexipag is classified as a selective, non-prostanoid prostacyclin (IP) receptor agonist.
It functions by binding to and activating the prostacyclin receptor, which mimics the vasodilatory and anti-proliferative effects of endogenous prostacyclin.
Unlike prostacyclin analogs, Selexipag has a different chemical structure but targets the same beneficial pathway for treating pulmonary hypertension.

Option B: Ambrisentan is an endothelin receptor antagonist (ERA), not a prostacyclin pathway drug. It works by blocking the vasoconstrictor effects of endothelin-1.
Option C: Epoprostenol is a prostacyclin analog, meaning it is a synthetic version of the prostacyclin molecule itself. The question specifically asks for a receptor agonist, which is a more precise classification for Selexipag.
Option D: Iloprost, like epoprostenol, is a prostacyclin analog. It mimics the action of prostacyclin but is not classified as a selective receptor agonist in the same way as Selexipag.

Visual 1: Flowchart - A flowchart illustrating the three main therapeutic pathways in pulmonary arterial hypertension: the prostacyclin pathway (targeted by agonists and analogs), the endothelin pathway (targeted by antagonists), and the nitric oxide pathway (targeted by PDE-5 inhibitors and guanylate cyclase stimulators). This helps visualize why the drugs are not interchangeable.

Clinical Relevance

Nursing practice connection: Knowing Pharmacology of Pulmonary Hypertension helps nurses interpret findings accurately and avoid errors in routine assessment, medication administration, and patient teaching.
Nurses must understand the different drug classes for pulmonary hypertension to educate patients on administration, side effects, and the importance of adherence. For example, IV prostanoids like epoprostenol require complex pump management and carry a high risk of catheter-related infections.
Monitoring for class-specific side effects is a key nursing role. For prostacyclin pathway drugs (including Selexipag), nurses monitor for headache, jaw pain, flushing, and diarrhea, and titrate doses carefully to manage these effects.
What if? If a patient develops severe injection site pain from subcutaneous treprostinil (another prostanoid), switching to an oral agent like Selexipag could be a therapeutic option to improve tolerance and quality of life, while still targeting the same beneficial pathway.

How to Approach the Question

First, identify the core of the question: it asks to classify a drug based on its specific mechanism of action ('prostacyclin receptor agonist').
Read the drug name in each option.
Recall or look up the pharmacological class for each drug. Pay close attention to precise definitions: 'receptor agonist' vs. 'analog'.
Ambrisentan is an endothelin receptor antagonist, so it's incorrect.
Epoprostenol and Iloprost are prostacyclin analogs. This is close, but not the most precise answer.
Selexipag is specifically known as a selective IP receptor agonist, which directly matches the question's terminology.

Concept Tested & Keywords

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