MDs are limited in supply by the AMA. NPs and PAs are not, and for routine cases, sore throats, minor injuries, vaccinations, routine physical exams, etc. there is no reason an MD needs to be involved.
And for the routine stuff I often have a pretty good idea what's ailing me from past experience and I just need someone to write up the prescription again for whatever's worked well before. I have no problems with seeing an NP for that.
In some cases, an NP may have more current experience with figuring out the routine stuff than an MD who's a bit more removed from that kind of practice now.
