631.Lignocaine (2 CORRECT)
A.Is a potent suppressor of normal cardiac activity
B.Appears to act exclusively on the Na channel
C.Has a Ca channel blocking effect
D.Has sympatholytic action
E.Has low first pass metabolism

A.Is a β1-selective adrenoceptor blocker
B.Has a bioavailability of ~ 50% due to first pass effect
C.Has no local anaesthetic action
D.Has class I antiarrhythmic properties only
E.Has class I and IV antiarrhythmic properties

A.Is a weak Ca blocker
B.Is an effective Na+channel blocker
C.Is anon-competitive inhibitor of β-receptors
D.Affects clearance of Warfarin and Digoxin
E.All of the above

A.Is only effective in the suppression of ventricular arrhythmia
B.Causes peripheral vasodilation via α adrenergic effects
C.Commonly causes corneal opacification
D.Increases warfarin clearance
E.Decreases AV nodal refractory period

A.Does not affect the delayed after potentials seen in digitalis toxicity
B.Preferentially blocks depolarizing Ca channels
C.Has a marked effect on the SA node as the tissue relies predominantly on Ca channels for impulse production
D.Its toxicity causes AV nodal block refractory to atropine
E.Is not associated with the development of peripheral oedema

A.Causes sinus tachycardia by both direct and indirect effects
B.Lengthens the QT interval by its effect on Na channels
C.Has no direct effect on K channels
D.Is largely excreted unchanged in the urine
E.Excretion is enhanced in alkaline urine

A.Is an orally administered anticoagulant with low bioavailability
B.Blocks the α carboxylation of glutamate residues in protein C
C.Has an anticoagulant action which is immediate
D.Does not cross the placenta-blood barrier
E.Causes increases PT

A.Consists of a heterogenous group of glycoproteins
B.Acts by decreasing activity of factor VII
C.Is associated with osteomalacia
D.Increases the reaction rate of antithrombin III on clotting factors
E.Is consumed in anticoagulant activity

639.The following drug causes cinchonism

640.Amiodaronelengthens the action potential primarily by
A.blocking Na channel in inactivated state
B.blocking K channels
C.weak Ca channel blockade
D.noncompetitive inhibitor of β receptors
E.peripheral vasodilation