· Digitalis acts in atrial fibrillation by:- Increase in AV node refractoriness.
· Major electrophysiological effect of digitalis is: 1) hyperpolarization
2) shortening of atrial action potential
3) increase in AV node refractoriness.
· Increase in AV node refractoriness is also responsive for termination of reentrant arrhythmias involving the AV node.
· Inhibition of Na+ K+ ATPase is responsible for inotropic action of digitalis.
Even in large dosages used in malaria, quinine does not cause toxicity because :-elevates plasma alpha1 acid glycoprotein .
· It is an erythrocytic schizontocide.
· Used for t/t of multidrug resistant strains of P.falciparum
· Associated with a triad of dose related toxicities- a)cinchonism b)hypotension c)hypoglycemia