Cardiovascular (Non-Cardioselective Beta-Blockers)

Question 1

Examples of drug (Non-Cardioselective Beta-Blockers)

Answer 1

• Propranolol

- Carvedilol

Question 2

Mechanism of action (Non-Cardioselective Beta-Blockers)

Answer 2

• Propanolol: Non-cardioselective beta-1-adrenoceptor antagonist.
• Carvedilol: Non-selective beta-1, beta-2 and alpha-1-adrenergic receptor antagonistic effects.
• Inhibits sympathetic stimulation in the heart and vascular smooth muscle.
• N.B Further details under Cardio-Selective Beta-Blockers.

Question 3

Indications (Non-Cardioselective Beta-Blockers)

Answer 3

• Hypertension
• Angina
• Anxiety
• Migraine prophylaxis
• Post-MI prophylaxis
• Carvedilol or Bisoprolol may be used as part of supportive therapy for mild / moderate heart failure.

Question 4

Side-effects (Non-Cardioselective Beta-Blockers)

Answer 4

• Bradycardia
• Hypotension
• Bronchospasm
• Fatigue (Can affect up to 10% of patients)
• Cold extremities
• Sleep disturbances
• Loss of hypoglycaemic awareness

Question 5

Important pharmacokinetics/pharmacodynamics (Non-Cardioselective Beta-Blockers)

Answer 5

• Caution in diabetic patients – risk of deranged carbohydrate metabolism
• Avoid in patients with Asthma and COPD – risk of bronchospasm
• Do not combine Beta-Blockers with rate-limiting Ca2+-Channel-Blockers (Verapamil / Diltiazem) in anti-hypertensive therapy.
• Propanolol is lipid-soluble and is predominantly cleared by the liver. Avoid in liver impairment. Avoid abrupt withdrawal – risk of liver impairment.

Question 6

Patient information (Non-Cardioselective Beta-Blockers)

Answer 6

• Nightmares and sleep disturbances may occur.
• Compliance is important – Patients may stop beta-blockers if they do not feel any better. Remind them that hypertension is asymptomatic but nonetheless a dangerous risk factor that needs controlled.
• Fatigue and cold extremities are common side-effects.