metoprolol

see also:

• beta adrenergic blockers

• metoprolol is a relatively cardioselective (ie. beta -1 receptor mainly) beta adrenergic blocking agent without intrinsic sympathomimetic activity.

• see beta adrenergic blockers

• rapidly absorbed from GIT
• rapidly and extensively redistributed to extravascular tissues
• 90% excreted in urine with 72hrs as metabolites
• elimination half life 3-5 hours
• duration of action is dose-dependent:
  • effects of 20mg iv dose falls to half by ~6hrs in healthy adullts

• tablets are usually 50mg or 100mg
• usual dose 100mg per day as either single dose or two divided doses (can increase to 150-200mg daily for severe hypertension)
  • initial dosing is often 50mg bd
  • some increase to 50mg tds for angina or migraine prophylaxis

• usually used iv for emergent Rx of tachyarrythmias including C-AF
• should be used with BP and cardiac monitoring
• initial iv dose is usually 5mg given over at least 1-2 minutes
• dose can be repeated as needed if no adverse effects, to max. 15-20mg