12-15-2014, 09:16 PM
Hi asaha ,
Use dependence is: more effect of the drug with more usage .Na channel is in 3 states >> resting , active and inactive ( resting and inactive are different).Rapidly depolarizing tissue spends more time in active and inactive states .
This is a good thing as long as we are trying to control arrythmia .However , in IC drugs ( flecainide aka passport to heaven ) it becomes a proarrythmic effect because drug is slow to dissociate from the channel which can slow the HR to the extent that it even exceeds the refractory period and in that case another action potential will be generated >>long story short >>arrythmia.
Use dependence is: more effect of the drug with more usage .Na channel is in 3 states >> resting , active and inactive ( resting and inactive are different).Rapidly depolarizing tissue spends more time in active and inactive states .
This is a good thing as long as we are trying to control arrythmia .However , in IC drugs ( flecainide aka passport to heaven ) it becomes a proarrythmic effect because drug is slow to dissociate from the channel which can slow the HR to the extent that it even exceeds the refractory period and in that case another action potential will be generated >>long story short >>arrythmia.