Hi there!
If you do a CPJE search around the forum, there are a lot of great advices.
What I did was going through RxPrep once. You should know all the therapeutics before you take CPJE. It's not a lot of law, at least for me (maybe around 20%), very little (and very very simple math, we're talking amoxicillin dispense how many ml type questions).
The therapeutics can be anything just like the NAPLEX. There were more HIV and ID proportion wise on the CPJE I feel like. Medication safety is huge. Make sure you know high-risk meds and reporting/med use improvement procedures (covered in RxPrep, I'd think other resources have it too). Know therapeutic interchange for major classes of meds (ACE-I, ARB, beta blockers, abx, etc). There were a few compatibilities questions (NS vs. D5W, light-sensitive, etc) but honestly I just couldn't memorize them all and probably got most of them wrong. I don't think they're make or break but if you have the time to get to memorize them, they're easy points.
I took the CPJE before the NAPLEX because I was worried about getting stuck in QA, so I came out feeling pretty horrible because it was my first major exam. In retrospect I don't think the CPJE was harder content-wise, but the passing rate is lower probably because the curving/cut off is less lenient.
If you're prepared for the NAPLEX, went over all your therapeutics plus the additional topics mentioned above then you should be OK. I bought RxPrep CPJE course and thought it was helpuful, not so much the videos but more for the quizzes; they help you identify your areas of weakness. Do do the sample test posted on the board's website, the format is the same. Again I wouldn't dwell too much on the law. Go over it the week before and you should be OK. Good luck!!!
