Pharmacokinetics of Sotalol and Propranolol Assignment

Pharmacokinetics of Sotalol and Propranolol - Assignment Example It is evidently clear from the discussion that Sotalol is an important anti-arrhythmic, class II/III drug. It is an oral drug with equal amounts of two enantiomers: D- and L--sotalol. Both enantiomers have the potency to act as non-selective blockers. The L – enantiomer gives greater benefits by acting as beta- blockade for a long-term period. L- Sotalol has 38% protein binding capacity and D-sotalol has 35% protein binding capacity. D-sotalol has no beta-blocking activity. The action potential of sotalol is due to the L-isomer and it also acts as alpha- blocker, while D-sotalol acts as anti-arrhythmic. D-sotalol has 30 to 60 times lower affinity than L-sotalol. On the other hand, in the case of Propranolol, there are two isomers: D and L – propranolol. D-propranolol binds to the proteins more extensively than L- propranolol. The L–isomer of propranolol is the biologically active form of the drug. It is nearly absorbed orally and metabolized in the liver on its f irst passage. D-propranolol is inactive in beta-adrenoreceptor blocking activity. So, it was observed that isomerism leads to many therapeutic and adverse drug reactions. D and L–propranolol have membrane stabilizing the property and this racemic mixture reduces the heart rate and the force of contraction in treated animals. The pharmacokinetic parameters of sotalol were studied in dogs and rats. Dogs had a higher volume of distribution and the elimination of the drug was through renal excretion. In rats, the high concentration of sotalol was observed in various tissues. The half-life of the drug was longer than other beta-adrenergic blockers in dogs. The beta blockade was observed without any change in the blood pressure in dogs.