Metoprolol vs Propranolol: what is the difference?

How they differ

Both are beta blockers and the difference is selectivity. Propranolol blocks beta-1 and beta-2 receptors alike, so alongside slowing the heart it also acts on airway and peripheral vessels, which is why it is used for tremor, migraine prevention and performance anxiety and why it is avoided in asthma. Metoprolol is relatively beta-1 selective, aiming at the heart and leaving the airways comparatively alone, though that selectivity fades at higher amounts. Propranolol is also far more fat-soluble, so it enters the brain readily, which is part of why it has a role in anxiety that metoprolol largely lacks. Metoprolol is the heavier at 267.36 against 259.34.

Side by side

Structural similarity 0.45 of 1, computed as a Morgan fingerprint Tanimoto coefficient. It measures shape, not effect.

Common questions

What is the difference between Metoprolol and Propranolol?

Both are beta blockers and the difference is selectivity. Propranolol blocks beta-1 and beta-2 receptors alike, so alongside slowing the heart it also acts on airway and peripheral vessels, which is why it is used for tremor, migraine prevention and performance anxiety and why it is avoided in asthma. Metoprolol is relatively beta-1 selective, aiming at the heart and leaving the airways comparatively alone, though that selectivity fades at higher amounts.

Is Metoprolol bigger than Propranolol?

Metoprolol is the heavier molecule, 267.36 g/mol against 259.34 g/mol for Propranolol. Metoprolol is C15H25NO3 and Propranolol is C16H21NO2.