Propranolol: The prototype beta-adrenergic blocker.

Question 1

Is propranolol selective?

Answer 1

No.

Question 2

Why is propranolol a pure antagonist?

Answer 2

Because it lacks any sympathomimetic activity.

Question 3

What receptors does propranolol work equally at?

Answer 3

B1 and B2

Question 4

How is propranolol administered?

Answer 4

In a stepwise manner until a goal of 55-60 bpm is achieved.

Question 5

Name the five cardiac effects

Answer 5

1. Decreased HR, contractility and CO.
2. The above effects are especially prominent during exercise and sympathetic outflow.
3. Blockade of B2 receptors: increases PVR (skeletal muscle), increased coronary vascular resistance.
4. Due to decreased HR and CO oxygen demand is lowered opposing the above effects
5. Sodium retention due to renal system response to drop in CO.

Question 6

The first pass effect of propranolol is significant. How much goes through? Meaning?

Answer 6

1. 90-95%

2. The oral dose is much larger than the IV dose.

Question 7

What is the dose of propranolol?

Answer 7

0.05mg/kg/IV or 1-10mg (give slowly 1mg every 5 minutes)

Question 8

How much of propranolol is protein bound?

Answer 8

90-95%.

Question 9

Where is propranolol metabolized? E1/2T?

Answer 9

1. Liver

2. 2-3 hours.

Question 10

Propranolol decreases the clearance of what because of a drop in hepatic blood flow/metabolism inhibition?

Answer 10

Amide LAs

Question 11

Propranolol decreases the pulmonary first pass effect of which drug?

Answer 11

Fentanyl