Beta- ADRENERGIC RECEPTOR ANTAGONISTS

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Effects of beta-adrenergic antagonists may be predicted from the consequences of b receptor stimulation (generally equivalent to the effects of elevated cyclic AMP). Effects of b antagonists at a particular site depend on the level of receptor stimulation, or tone, at that site. Effects of antagonists are more prominent when receptor stimulation by agonist is high.

Beta-Adrenergic antagonists may be classified as
  • Non-Subtype Selective (First Generation)-( Nadolol ,Penbutolol ,Pindolol ,Propranolol ,Timolol)
  • Beta 1-Selective (Second Generation), - (
    Acebutolol, Atenolol, Bisoprolol, Esmolol, Metoprolol) and
  • Antagonists with Additional Cardiovascular Actions (Third Generation).
  1. Nonselective b blockers with additional actions: Third generation (Carteolol, Carvedilol, Labetalol)
  2. Beta1-selective b blockers with additional actions: Third generation (Betaxolol, Celiprolol)

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