Makindo Medical Notes

Related Subjects: |Hypertension |Acute Heart Failure |Chronic Heart Failure

Use IV must be with close cardiac and physiological monitoring.

About: Always check the BNF link here

• Block Beta-adrenergic receptors in heart, peripheral vessels, lungs, pancreas and liver

Indications

• Hypertension - reduced Cardiac output, block peripheral receptors, some reduce plasma renin activity. Full dose often not needed.
• Angina - reduces cardiac oxygen demand. Avoid verapamil as can precipitate heart failure
• Post-MI - STEMI and NSTEMI can reduce mortality
• AF rate control - reduce automaticity and conduction. Use with or instead of Digoxin.
• Thyrotoxicosis - useful to control sympathetic symptoms
• Anxiety, Benign essential tremor

Dose

• Hypertension: Metoprolol 100-200 mg od PO (max rarely needed 400 mg od)
• Angina: Metoprolol 50-100 mg bd or tds PO
• Arrhythmias: Metoprolol 50-100 mg bd or tds PO
• Migraine prevention: Metoprolol 50-100 mg bd PO
• Hyperthyroidism: Metoprolol 50 mg qds PO
• Post MI: Metoprolol 5 mg slow IV every 5 minutes as tolerated. (Max dose 10-15 mg). Start Oral Beta-blocker e.g. Bisoprolol once daily as a regular therapy.
• Fast AF: Metoprolol 1-5 mg IV at a rate not exceeding 1 mg per minute. Reassess after 5 minutes and repeat if required. (Max dose 10-15 mg). Start Oral Beta-blocker e.g. Bisoprolol once daily as a regular therapy.

Metoprolol and AF

• Metoprolol is preferred for intravenous administration given its short half-life, it is given as a bolus injection, without dilution at a rate not exceeding 1 mg per minute. Titrate up to 5 mg initially, reassess after 5 minutes and repeat if required. If no ill effects observed, administer 25 mg orally and commence 2.5 mg bisoprolol once daily as a regular therapy. This can be titrated up to a maximum dose of 20 mg once daily

Dose range:You must check with BNF or drug datasheet

Name	Dose Range	Frequency	Route
Metoprolol (CCF/AF/Hyperthyroid)	25-100 mg	BD	PO
Metoprolol (HTN/Angina)	50-100 mg	BD	PO
Metoprolol (post MI)	5 mg every 2 mins up to 15 mg on telemetry	stat	IV then start oral dose 50 mg 6 hourly
Metoprolol (Fast AF)	5 mg reassess after 5 minutes and repeat if required.	stat	Slow IV rate not exceeding 1 mg per minute

Contraindications

• Bradycardia <60bpm, systolic BP <100mmHg
• Asthma/Bronchospasm
• 2nd or 3rd degree heart block
• Avoid in Diabetes especially with thiazide
• Uncontrolled Heart failure
• Severe hypotension
• Phaeochromocytoma except with an alpha blocker
• Sick sinus syndrome
• Significant peripheral vascular disease
• Concomitant use of verapamil

Side effects

• Fatigue, Cold peripheries, Worsening diabetic control
• Postural hypotension, Dizziness, Worsening psoriasis, Impotence
• Claudication, Insomnia

References

• Metoprolol at BNF