Metoprolol antiarrhythmic activity

Qass II antiarrhythmic drugs are beta-blockers that decrease SA and AV nodal activity, decrease the phase 4 slope, and prevent p, adrenocepter activation, thereby circumventing the normal increase in cAMP. Propranolol is nonselective acebutolol, metoprolol, and esmolol are selective. Their antiarrhythmic use is discussed. 

Beloc-Zok H 93/26 succinate Metoprolol succinate Seloken ZOC Selozok Spesicor Dos Toprol XL. A p-adrenergic blocker. Lacks inherent sympathomimetic activity. Antianginal class II antiarrhythmic anti-hypertensive. Apothecon Astra Chem. Ltd. Astra Sweden Ciba-Geigy Corp. Lemmon Co. 

Differences in metabolism among patients can lead to differences in susceptibility to ADRs e.g. patients with abnormal pseudocholinesterase levels have prolonged apnea after receiving succi-nylcholine patients with low activity of A-acetyl transferase are more likely to develop lupus-like reactions to procainamide, hydralazine, and isonia-zid and variants of the cytochrome P-450 family of enzymes can lead to altered metabolism of a variety of drugs, including antidepressants, antiarrhythmic agents, codeine, metoprolol terfenadine, cyclosporine, calcium channel blockers, and others (Peck et al 1993). 

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