Step I Morphine MOAs?

[Ophthoseidon]

I got a UWorld question wrong because I wasn't sure of the mechanism. I thought i remembered reading (or hearing) that morphine does affect VG sodium channels, so I picked that answer. I understand their explanation about the mu receptor pathway of potassium efflux, but I did a google search and it looks like morphine also affects VG slow sodium channels.

So wtf?

Also, only 29% of people got it right when 40% picked sodium so somethings gotta give

 

[worldbeater]

All opoids MOA is usually potassium efflux. That should be your go to answer.

Also, whenever you see a patient present with "weakness" or something related to that in the stem and they are asking about what ions are in play, think of potassium efflux. There is more than 1 World Q you can easily get a point on by knowing this.