Which of the following is a methylxanthine group of

bronchodilators?

Appeared in: UPPSC 2017

Explanation

Aminophylline is a compound of theophylline and ethylenediamine, belonging to the methylxanthine class of drugs.
Methylxanthines act as bronchodilators by relaxing the smooth muscles of the bronchial airways.
Their mechanism involves the inhibition of the phosphodiesterase enzyme, which increases intracellular cyclic AMP (cAMP) levels, leading to smooth muscle relaxation and bronchodilation.
While effective, their use has declined due to a narrow therapeutic index and the availability of safer alternatives like beta-2 agonists.

Option A: Terbutaline is a sympathomimetic drug, specifically a short-acting beta-2 adrenergic agonist (SABA), not a methylxanthine.
Option C: Salmeterol is also a sympathomimetic drug, but it is a long-acting beta-2 adrenergic agonist (LABA), not a methylxanthine.
Option D: Ipratropium is an anticholinergic (or antimuscarinic) agent. It causes bronchodilation by a different mechanism than methylxanthines.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Pharmacological Classification of Bronchodilators as background academic context rather than a clinical decision trigger.
Nurses must be knowledgeable about the different classes of bronchodilators to ensure safe administration, educate patients on correct usage (e.g., reliever vs. controller inhalers), and monitor for class-specific side effects.
Aminophylline has a narrow therapeutic index, meaning the dose required for therapeutic effect is close to the toxic dose. Nurses must diligently monitor patients for signs of toxicity, which include tachycardia, nausea, vomiting, and seizures. Therapeutic drug monitoring (checking blood levels) is often required.
Patient education is crucial. For instance, a patient using Salmeterol (a LABA) must understand it is for long-term control and should not be used for an acute asthma attack, for which a SABA like Terbutaline or Salbutamol is needed.

How to Approach the Question

First, identify the key concept in the question stem, which is the 'methylxanthine group' of bronchodilators.
This is a factual recall question that tests your knowledge of pharmacology and drug classification.
Systematically review each option and try to recall its drug class.
Recall or deduce that Terbutaline and Salmeterol are beta-2 agonists (sympathomimetics).
Recall or deduce that Ipratropium is an anticholinergic drug.
Identify Aminophylline as the drug belonging to the methylxanthine class.

Concept Tested & Keywords

QEDXjOCejJanGf3XPop7TC

E6 Pharmacology Nurses Shanbhag 3e p. 202-204

E6 Pharmacology Katzung 16e p. 564-566

E6 Pharmacology KD Tripathi Essentials 9e Part 1 p. 269-271

Practise the full UPPSC 2017

Attempt every question from this paper in a timed mock, then review the full solution for each one.