Beta blockage leads to ↓Gs activity in receptor associated organs and
associated ↓ in adenylyl cyclase and intracellular Ca2+.

Binds to V binding site of L-type channel.
Levoisomer: main effects (arterial vasodilation). Slows conduction through the AV and SA node to a greater extent than other CCBs.
Dextro: Only acts on fast sodium channels, accounting for local anesthetic effects (1.6x potent as procaine)

It produces
decreases in heart rate and cardiac output and myocardial oxygen consumption.

Whilst it does have some β 2 action it has little or no effect on these receptors
at doses less than 100mg

CVS: slow conduction of AP at SA and AV node, negatively inotropic, peripheral vasodilation (↓ SVR), arrhythmia (heart block, VF in WPW). CNS: ↑ CBF, may potentiate effects of depol/NDMBs. GIT - Constipn/Nausea

bioavailabilty Absoption is rapid and complete, however there is extensive fi¬rst pass metabolism bioavailability = 50%

Completely absorbed orally. Oral bioavailability 10-22% because of significant first-pass metabolism.

lipid solubility is high so it crosses the BBB

10-20% to albumin

~90%

5.5 L/Kg

3.89 L/kg

hepatic or renal Extensively hepatic via CYP2D6

Hepatic via multiple CYP isoenzymes, one active metabolite with 20% activity

urine 5-10% unchanged

Urine (70% metab, 3% to 4% unchanged); feces (16%)

3-8hours

3-7 hours

- Withdrawal

- Care with: Opioids, Halo, OAD, CCB

- Use with Ca Channel blockers may result in complete heart block

Dizziness, nausea, flushing, postural hypotension.
in patients without CCF: ↑ LV fn by improving ischemia. In pts with CCF: ↓ contractility and LV fn. Should be avoided in pts with WPW- cause VT/VF.
Inhibits CYP3A4.

Racemic mixture.

Selective beta1-adrenoceptor antagonist; Vaughan Williams class II antiarrhythmic.

Non-dihydropyridine calcium-channel blocker; Vaughan Williams class IV antiarrhythmic.

- Early use of metoprolol in haemodynamically stable myocardial infarction reduces infarct size and incidence of VF.
- rate control in atrial -fibrillation
- hypertension

HTN
Angina
Paroxysmal SVT and AFib/Aflutter

relatively selective beta blocker with no intrinsic sympathomimetic activity.

Phenylalkylamine
(Non-dihydropyridine calcium channel blocker)

Synthetic papaverine derivative

Level 3

Level 3

on/ dur 1-2 hrs / 6-8 hrs (PO)

available in oral form as an immediate release or sustained release in
increments of 25mg.
It is also available as an IV formulation usually 1mg/ml

Available in oral immediate/modified-release formulations and as an IV preparation; exact strengths vary by product.

PO or IV
dose Orally in 12.5mg increments, IV in 1-2mg boluses

40mgPO or 5-10mg IV.