641.Warfarin will be potentiated by all of the following except
A.Amiodarone
B.Cimetidine
C.Diazepam
D.Metronidazole
E.Fluconazole

642.LMWH
A.MW = 15 000
B.Inhibits activate factor X
C.Has unpredictable pharmacokinetics
D.Can be used with minimal problems in renal failure
E.Is readily reversedwith protamine

643.The following type 1 Na+channel blocker shortens action potential
A.Quinidine
B.Lidocaine
C.Flecainide
D.Procainamide
E.Disopyramide

644.The following diuretics may have cross-allergy due to sulphur groups except
A.Acetazolamide
B.Chlorothiazide
C.Frusemide
D.Bumetanide
E.Amiloride

645.The most common adverse effect of a thiazide is
A.low K
B.Mg depletion
C.Impaired glucose tolerance
D.Increased lipids
E.Gout

646.The following IV antihypertensive also inhibits insulin release
A.Hydralazine
B.SNIP
C.Diazoxide
D.Labetalol
E.Fenoldopam

647.Regarding Ca channel blockers which is false
A.Skeletal muscle is not depressed
B.Nimodipine has high affinity for cerebral blood vessels
C.Verapamil also causes Na channel block
D.All act via T type Ca channels
E.Excess effects include cardiac arrest, bradycardia and AV block

648.Nitrates primarily cause relief of angina via
A.Relaxation of arterioles and arteries
B.Relaxation of veins and reduced preload
C.Reduction of afterload
D.Increased collateral flow
E.Dilation of coronary epicardial vessels

649.The major electrical actionof digitalis includes all except
A.Increase refractory period at AV node
B.Increased automaticity
C.Decreased PR interval
D.Decreased refractory period at atria and ventricles
E.Negligible effect on conduction velocity in ventricles

650.Digoxin toxicity is more likelyin all except
A.Low K
B.High Ca
C.Quinidine therapy
D.Antibiotics
E.High Mg