66 - Beta blockers

*Beta blockers are drugs which act against the beta adrenergic receptors. There are three kinds of adrenergic receptors namely beta1, beta2 and beta3.

*First generation beta blockers (non-selective beta blockers) :
- Propranolol
- Nadolol
- Timolol
- Penbutalol
- Pindolol
- Oxprenolol
- Alprenolol

*Second generatin beta blockers ( Beta1 selective beta blockers = Cardioselective beta blockers ):
- Acebutalol
- Celiprolol
- Bisoprolol
- Metaprolol
- Nebivolol (most cardioselective beta blocker)
- Atenolol
- Esmolol
- Betaxolol

*Third generation beta blockers ( These are beta blockers which have additional vasodilator property ):
- Labetalol and Carvedilol ( act as vasodilators by antagonising alpha1 receptors on blood vessels)
- Tilosolol ( act as vasodilator by opening up potassium channels)
- Nebivolol and Nipradilol ( generate Nitric oxide )
- Bevantolol, Betaxolol, Carvedilol ( inhibit calcium channels )
- Bopindolol, Carteolol, Celiprolol ( agonists of beta2 receptors )

* Beta blockers with Membrane stabilising activity (local anaesthetic activity) :
- Propranolol (most effective)
- Labetalol
- Acebutolol
- Metaprolol
- Pindolol

* Beta blockers with intrinsic sympathomimetic activity :
- Oxprenolol
- Alprenolol
- Pindolol
- Celiprolol

* Beta blockers which are lipid insoluble ( so they are excreted by kidney and hence contraindicated in renal failure - LONG ACTING AGENTS ) :
- Nadolol
- Sotalol
- Acebutalol
- Atenolol
- Betaxolol
- Bisoprolol
- Celiprolol

* Longest acting beta blocker is Nadolol
* Shortest acting beta blocker is esmolol.