Beta-adrenoceptor blocking drugs (beta-blockers)

Question 1

Beta-blockers and carbohydrate metabolism

Answer 1

Beta-blockers can affect carbohydrate metabolism.
This can cause hypo- or hyperglycaemia in patients with or without diabetes.
They can mask the symptoms of a hypo in diabetic patients.

Question 2

Bronchospasm

Answer 2

• Usually avoided in patients with a history of asthma or bronchospasm.
• If no alternative, a cardioselective beta-blocker (atenolol, bisoprolol, metoprolol, nebivolol) can be given under specialist supervision.

Question 3

Bradycardia

Answer 3

Excessive bradycardia can occur with IV injection.
Symptoms:
- Fatigue
- Dizziness/lightheadedness
- Fainting
- SoB

Question 4

Beta-blockers + Verapamil

Answer 4

Should not be given together.
Risk of hypotension and asystole.

Question 5

Labetalol

Answer 5

Hypertension in pregnancy
Monitor liver function.
Risk of severe hepatocellular damage.
Associated with short + long term treatment.
If hepatotoxicity confirmed - DISCONTINUE

Question 6

ice PACO

Answer 6

INTRINSIC sympathomimetic activity.
- Less bradycardia
- Less coldness of the extremities

Pindolol
Acebutlol
Celiprolol
Oxprenolol

Question 7

water CANS

Answer 7

WATER-SOLUBLE. Less likely to cross blood-brain barrier.
- Less nightmares and sleep disturbances.
- Reduce dose in renal impairment (renally cleared).

Celipolol
Atenolol
Nadolol
Sotalol (class 3 anti-arrhymthmic. SE = torsade de pointes)

Question 8

Be A MAN

Answer 8

CARDIO-SELECTIVE = less bronchospasm.
- Well controlled asthma under a specialist if no other choice.

Bisoprolol
Atenolol
Metoprolol
Acebutolol
Nebivolol

Question 9

Contraindications

Answer 9

• Asthma - causes brncospasm (includes B-Blocker eye drops e.g. timolol .
• Worsening unstable HF
• 2nd/3rd degree heart block
• Severe hypotension + bradycardia