B-blockers selectivity

 Q: Which of the following is a selective beta-1 adrenergic blocker? (select one)

A) atenolol 

B) propranolol

Answer:  A 

Atenolol being a selective beta-1 adrenergic blocker can be alternatively used where beta-blockers can not be used due to the effect on B--2 receptors such as asthma or bronchospasm. One of the drawbacks of atenolol is that its efficacy goes down at a higher dose i.e., above 100 mg per day. 

It is a drug with decades of experience and uses worldwide in a wide range of clinical conditions including angina, hypertension, rate control in atrial fibrillation/flutter, Marfan syndrome with an aortic aneurysm, migraine prophylaxis, thyrotoxicosis, anxiety, and essential tremor. 

Interestingly, in clinical practice atenolol is prescribed more for off-label uses than approved indications. 

#pharmacology

References:

1. Lin HW, Phan K, Lin SJ. Trends in off-label beta-blocker use: a secondary data analysis. Clin Ther. 2006 Oct;28(10):1736-46; discussion 1710-1. doi: 10.1016/j.clinthera.2006.10.015. PMID: 17157130.

2. Rehman B, Sanchez DP, Shah S. Atenolol. [Updated 2020 Oct 6]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK539844/