"Advanced practice nurse" (or "nursing") is a generic term because there are four categories of APNs -- nurse practitioners (with a variety of available specialties within the general category), clinical nurse specialists (ditto), certified nurse anesthetists (CRNAs), and certified nurse midwives (CNMs).
There are many older threads here that you can search and find that discuss the similarities and differences between NPs and CNSs. I would have been able to give you a clear and straightforward answer a few years ago, but, in psych esp., the roles have become so similar/blurred in recent years that I'm honestly no longer sure of how to explain the difference.
My concern is not just that, in the larger mental health community, the pendulum has swung from therapy to a biological/pharmacological focus, but that the people who are being prepared nowadays as psych NPs and CNSs are supposedly (allegedly
being prepared as psychotherapists, but they are getting only a small fraction of the education and supervised cliinical experience in psychotherapy that we "old-timer" psych CNSs got, because the programs now are primarily focused on preparation for Rxing ...
I look at it this way (admittedly, v. politically incorrect in nursing circles, but I don't care
; I've been in nursing 'way too long to just hop onto whatever bandwagon comes along) -- traditional (primary care ("medical," not psych) focused) NP programs are 2-year MSN programs. Traditional psych CNS programs are (were!) 2-year MSN programs. Psych NP (and, nowadays, most psych CNS) programs supposedly combine both roles -- but they're not 4-year programs; they are also
2-year MSN programs. So, doesn't that mean that you're getting half
an NP program and half
a CNS program (at best)? Do these programs really prepare people adequately for either
role (Rxing and/or therapy)?? And because, obviously, the Rxing piece is the greater risk/obligation (people can die if you don't get it right), the programs focus on that and appear (from the curricula I've looked at lately) to offer only minimal coursework in therapy, almost as an afterthought.
Other posters here may have different experiences and viewpoints (I know they do, in fact), and people who are in private outpatient practice have a great deal of control over how they divide their time between Rxing and doing therapy, but, now that psych NPs/CNSs are out there with prescriptive authority, many agencies consider their time much too valuable to be conducting therapy when they could be writing scripts. Many agencies (both inpatient and outpatient settings) only want to use psych NPs in the physician extender role, to see clients for 15 minute med management appointments like the psychiatrists do, and hire lower-cost social workers and LPCs to be psychotherapists. If you look around (or have already done so), you'll notice that very
few psychiatrists do any psychotherapy at all (and, again, their training has adjusted to reflect that reality over the years; they now get v. little training in therapy, so they wouldn't be competent to do it if they wanted
to) -- they (quickly) diagnose people and Rx meds, and hand the clients off to others for therapy. That is the direction I see advanced practice psych nursing going ("psychiatrist Lite" just as the NPs have always been "physician Lite"). It's not a role that interests me, personally, at all, but to each her/his own ... Obviously, this is the wave of the future and I'm now, officially, an outdated old fogey.
As for employment opportunities and job availability, that varies greatly from region to region around the country, so I can't really speak to that. I do feel confident saying that, if you choose to pursue education as a psych NP or CNS, be aware up front that you will spend most of your time studying physical assessment, pharmacology, and medical management, not
psychotherapy. You can easily do a web search for universities offering psych MSN programs (many schools
now offer a combined NP/CNS program that prepares you for either certification exam) and see what their curricula look like.