BETA ADRENOCEPTOR BLOCKERS OH CH 2 CH CH

BETA ADRENOCEPTOR BLOCKERS

OH CH 2 CH CH 3 CH 2 NHCH CH 3 PROPRANOLOL OH CH 3 OCHCH 2 OCH 2 CH CH 3 CH 2 NHCH CH 3 METOPROLOL

CLASSIFICATION OF BETA BLOCKERS Ø NON - SELECTIVE ( 1, 2) BLOCKERS ¨ PURE BLOCKERS v SOTALOL v TIMOLOL v NADOLOL ¨ WITH MEMBRANE STABILIZING ACTIVITY (MSA) v PROPRANOLOL ¨ WITH INTRINSIC SYMPATHETIC ACTIVITY (ISA) v PINDOLOL (MSA ) v CARTEOLOL v PENPUTALOL ¨ WITH ISA & MSA v OXPRENOLOL

Ø CARDIOSELECTIVE ( 1) BLOCKRES ¨ PURE BLOCKERS v ATENOLOL v BISOPROLOL v ESMOLOL ¨ WITH MSA v METOPROLOL v TOLAMOLOL ¨ WITH ISA v PRACTOLOL (Clinically not used now) v CELIPROLOL ¨ WITH ISA & MSA v ACEBUTOLOL Ø DRUG THAT BLOCK BOTH & RECEPTORS v LABETALOL v CARVEDILOL v BUCINDOLOL

BETA ADRENOCEPTOR BLOCKERS PHARMACOKINETIC PROPERTIES LIPID/WATER SOLUBILITY LIPID SOLUBLE PROPRANOLOL TIMOLOL METOPROLOL PENBUTOLOL WATER SOLUBLE NADOLOL ATENOLOL ACEBUTOLOL

DURATION OF ACTION ULTRA SHORT ACTING Half Life ESMOLOL 9 Minutes INTERMEDIATE ACTING PROPRANOLOL TIMOLOL PINDOLOL METOPROLOL 3 - 5 HOURS 3 - 4 HOURS LONG ACTING NADOLOL ATENOLOL BISOPROLOL 10 - 20 HOURS 5 - 8 HOURS 11 - 17 HOURS

Pharmacological effects n CVS n Respiratory system n Kidney n Metabolic effects n CNS n Peripheral n Eye n Ankle jerk nervous system

THERAPEUTIC USES OF BETA ADRENOCEPTOR BLOCKERS u CARDIOVASCULAR DISEASES Ø Hypertension (Cardio-protective) Ø Angina pectoris (Prophylaxis) Ø Myocardial infarction v Primary prevention v Limit the size of infarct v Secondary prevention Ø Cardiac arrhythmias ØCongestive Cardiac Failure Beta 1 selective e. g. Metoprolol & Bisoprolol Non selective e. g. carvedolol (Contd)

Ø Obstructive Cardiomyopathies v Hypertrophic sub aortic stenosis v Fallot’s tetrology Ø Dissecting aneurysm of aorta Ø Portal hypertension Ø Sub arachnoid hemorrhage

u u CONDITIONS ASSOCIATED WITH SYMPATHETIC OVER- ACTIVITY Ø Thyrotoxicosis Ø Acute anxiety states (Panic syndromes) Ø Childhood phobias Ø Acute porphyria Ø Drug withdrawal syndrome Ø Pheochromocytoma (alongwith alpha blockers) Miscellaneous Ø Glaucoma (Simple open angle) Levobunolol, Betaxolol, Timolol Ø Migraine (Prophylaxis) Ø Familial Tremors

ADVERSE EFFECTS n CVS Cardio depression, Bradycardia, Heart Blocks, Cardiac Failure Cold extremities, Worsening of Peripheral Vascular Disease n RESPIRATION Bronchospasm n CNS Sleep disturbances, Nightmares n METABOLIC Masking of Hypoglycemia Increased TGs, Reduced HDL n Male Sexual Dysfunction n Rashes, Diarrhoea, Muscle cramps n Oculomucocutaneous syndrome- practolol

DRUGS INTERACTIONS n n n n n Enzyme inhibitors – Cimetidine Chlorpromazine, hydrallazine, furesimide Enzyme inducers Sympathomimetics Prazosin Clonidine Lignocaine Calcium channel blockers NSAIDs e. g. Indomethacin Antihypertensives

TREATMENT OF OVERDOSAGE n Atropine n Beta adrenoceptor agonists e. g. isoprenaline, dobutamine, dopamine n Glucagon CONTRAINDICATIONS