Question:easy
In which of the following conditions should propranolol NOT be used?
In which of the following conditions should propranolol NOT be used?
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Non-selective beta blockade removes bronchodilator tone and can trigger bronchospasm, so propranolol is avoided in asthma.
Updated On: Jul 8, 2026
- Asthma
- Panic attack
- Premature ventricular contractions (PVCs)
- Hypertrophic cardiomyopathy
Show Solution
The Correct Option is A
Solution and Explanation
Step 1: Sort the four conditions by whether beta blockade helps or hurts.
Propranolol's effect depends on which receptors are dominant in the problem being treated, heart-related conditions generally benefit, airway conditions generally suffer.
Step 2: Look at the heart related options first.
Panic attack symptoms like a racing heart and shaking are driven by excess sympathetic (beta) activity, so blocking beta receptors calms these symptoms. PVCs come from abnormal excitability in heart muscle, and reducing sympathetic drive with a beta blocker can quiet the extra beats. Hypertrophic cardiomyopathy causes outflow obstruction that gets worse with a fast, forceful heartbeat, so slowing and softening contraction with a beta blocker actually reduces the obstruction. All three of these are settings where propranolol is useful.
Step 3: Now look at the airway.
Propranolol does not choose only heart receptors, it also blocks beta-2 receptors in the airway smooth muscle. Those receptors normally keep the airway relaxed. Removing that relaxing signal in someone with asthma can bring on a dangerous bronchospasm.
Step 4: Conclude.
Because of this airway risk, asthma is the one condition on the list where propranolol should not be used.
\[ \boxed{\text{Asthma}} \]
Propranolol's effect depends on which receptors are dominant in the problem being treated, heart-related conditions generally benefit, airway conditions generally suffer.
Step 2: Look at the heart related options first.
Panic attack symptoms like a racing heart and shaking are driven by excess sympathetic (beta) activity, so blocking beta receptors calms these symptoms. PVCs come from abnormal excitability in heart muscle, and reducing sympathetic drive with a beta blocker can quiet the extra beats. Hypertrophic cardiomyopathy causes outflow obstruction that gets worse with a fast, forceful heartbeat, so slowing and softening contraction with a beta blocker actually reduces the obstruction. All three of these are settings where propranolol is useful.
Step 3: Now look at the airway.
Propranolol does not choose only heart receptors, it also blocks beta-2 receptors in the airway smooth muscle. Those receptors normally keep the airway relaxed. Removing that relaxing signal in someone with asthma can bring on a dangerous bronchospasm.
Step 4: Conclude.
Because of this airway risk, asthma is the one condition on the list where propranolol should not be used.
\[ \boxed{\text{Asthma}} \]
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