Saturday May 15, 2010

Q: What is the conversion (or equivalent) of propranolol to Nadolol in portal hypertension?


Answer: Decrease the dose to half and give once a day.

In portal hypertension treatment, Beta-blockers are noncardioselective and reduce portal and collateral blood flow by 2 methods

• Reduction in cardiac output (blockade of beta1-adrenoreceptors) occurs.
• Splanchnic vasoconstriction (blockade of vasodilatory adrenoreceptors of the splanchnic circulation).

Most commonly used noncardioselective B-blockers are propranolol and Nadolol.

Propranolol is usually started at a dose of 20 mg every 12 hours, and increased or decreased every 3-4 days until a 25% reduction in the resting heart rate occurs or the heart rate is down to 55 beats per minute (bpm). The average dose of propranolol usually is 40 mg bid.

Nadolol dosing is half the daily dose of propranolol, administered once a day.