Makindo Medical Notes

⚠️ IV use must only be undertaken with close cardiac and physiological monitoring.

📖 About

Always check the BNF link here for up-to-date dosing.

• Beta-blockers block beta-adrenergic receptors in the heart, vessels, lungs, pancreas, and liver.
• Atenolol is more lipid-soluble, with potentially more CNS side effects.
• It is relatively cardio-selective (greater effect on β1 than β2 receptors).

🎯 Indications

• Hypertension → lowers cardiac output, blocks peripheral receptors, reduces plasma renin activity (often effective at low dose).
• Angina → reduces cardiac oxygen demand. ⚠️ Avoid verapamil co-prescription (risk of heart failure).
• Post-MI (STEMI/NSTEMI) → reduces mortality.
• Arrhythmias → decreases automaticity and AV conduction. May be used with or instead of digoxin for AF rate control.
• Thyrotoxicosis → controls adrenergic symptoms (tachycardia, tremor).
• Heart failure → only bisoprolol, carvedilol, and nebivolol (in ≥70 years, mild/moderate HF) reduce mortality.

💊 Indications & Dosing Atenolol

• ACS/Post-MI/Arrhythmias (IV): 2.5–5 mg slow IV over 5–10 min (1 mg/min rate), may repeat after 15 min up to 10 mg.
• ACS/Post-MI (PO): 25–100 mg daily.
• Hypertension: 25–50 mg once daily.
• Angina: 50–100 mg daily (single or divided doses).
• Arrhythmias (PO): 50–100 mg daily (single or divided doses).

⚠️ Dose range: Always confirm with the BNF or drug datasheet.

⛔ Contraindications

• Bradycardia (<60 bpm) or systolic BP <100 mmHg.
• Asthma/bronchospasm.
• Second- or third-degree heart block.
• Uncontrolled, decompensated, or acute severe heart failure.
• Severe hypotension.
• Phaeochromocytoma (unless combined with an α-blocker).
• Sick sinus syndrome.
• Significant peripheral vascular disease.
• Diabetes mellitus (especially if also on thiazide diuretics – masks hypoglycaemia).
• ⚠️ Concomitant use with verapamil (risk of complete heart block).

⚠️ Side Effects

• Fatigue, lethargy.
• Cold peripheries, bradycardia, hypotension.
• Heart failure, conduction abnormalities.
• Bronchospasm.
• Impotence, reduced exercise tolerance.
• Worsening diabetic control (masks hypoglycaemia symptoms).
• Worsening of psoriasis in susceptible patients.

📚 References

• Atenolol in BNF
• Oxford Handbook of Clinical Medicine.
• ESC Guidelines on Hypertension & ACS.