Beta blockers

Question 1

Propranolol

Answer 1

Nonselective beta blocker
Blocks both B1 and B2 adrenergic receptors–> B1: reduces heart rate, myocardial contractility, and conduction velocity which lowers cardiac output and blood pressure
B2: affects smooth muscles in the airways and blood vessels

It crosses the BBB (lipophilic)
USES: AMI, migraine prophylaxis, membrane stabilizing effect (Na+ channel blocker)

Question 2

Pindolol

Answer 2

Nonselective beta blocker
It has a strong intrinsic sympathomimetic activity (ISA), membrane stabilizing effect (Na+ channel blocker), less imapairment of lipid profile

Used primarily to treat high blood pressure and other cardiovascular conditions

ISA: pindolol has mild agonistic activity at beta receptors which means it can partially stimulate these receptors while also blocking them. This can help reduce some of the typical side effects associated with other non selective beta blockers such as bradycardia and reduced cardiac output

Question 3

Carvedilol

Answer 3

Beta blocker effects:
*Membrane stabilizing effect (Na+ channel blocker)
*Less impairment of lipid profile (meaning its less likely to negatively effect blood lipid levels compared to other antihypertensive medications, particularly certain beta blockers
*Used in congestive heart faliure

Question 4

Timolol

Answer 4

Nonselective beta blocker
Used as eye drops for glaucoma

Question 5

Sotalol

Answer 5

Nonselective beta blocker
It is a K+ channel blocker - type III antiarrhythmic agent: SVT (supraventricular tachycardia), VT (ventricular tachycardia)

The K+ channel blocker effect of sotalol—> prolongs the action potential and refractory period–> managing arrhythmias
It is a hydrophillic compound

Question 6

Metoprolol

Answer 6

Beta1 selective antagonist (cardioselective)
It is given orally (tablet) or injection (i.v)
All cardiovascular indications, migraine prophylaxis (lipophilic), hyperthyroidism

It is used in hyperthyroidism as a symptom control as hyperthyroidism causes tachycardia

Question 7

Bisoprolol

Answer 7

Beta1 selective antagonist (cardioselective)
Used for hypertension, chronic stable agina, congestive heart failure

Question 8

Nebivolol

Answer 8

Selective beta1 antagonist (cardioselective)
NO releaser also: vasodilation
Better for young adult men, impotence risk is low (lower likelihood of causing erectile dysfunction)

USE: hypertension, congestive heart failure

Question 9

Esmolol

Answer 9

Selective beta1 antagonist (cardioselective)
I.V infusion, short half life (about 9 min), SVT, atrial fibrillation - flutter, perioperative hypertension/tachycardia

The short half life is useful in acute situations as it has a rapid onset and a quick offset action