Thought I'd throw in my 2 cents, for what it's worth. Originally, when I decided to pursue admission to a CRNA program, my thinking was that I should have basically the same prerequisites that any pre-med student should have: 2 semesters of general or inorganic chemistry, 2 semesters of organic, 2 semesters of biology, and 2 semesters of physics. So this past summer I took 2 semesters of general chemistry (my original chemistry was at UMass Amherst 25 years ago...needed a little refreshing...)(what a way to spend the summer...yeesh... 1 year of chemistry in 13 weeks. I would not recommend it.) My plan was to take organic in the coming fall and spring semesters. HOWEVER, I'm realizing a few things. If you are applying to an MSN school; one that requires a BSN and delivers and MSN - they usually don't require much chemistry beyond what is taken in nursing school (which often is, unfortunately, not as demanding as the "science major" chem.) I believe I saw Kevin M say somewhere that he was told "we'll teach you all the chemistry you need to know" which is probably true. Schools that deliver a MS of some sort - a non-MS Nursing school - more likely desire the additional chemistry, usually just one semester of organic, or even a biochem. For me, as these are the schools I will most likely be applying to, I will be taking the organic.
I think in general, you want to make yourself as competitive as you can. If you are going the non-BSN route, it could not hurt to show the strongest science background you are capable of. Chemistry is a pain in the ...neck...(!) but learning it, I believe, will provide a broader background which will help anyone be a better clinician.. which is, after all, the point... even if the gpa drops slightly.
Now, having said all this, keep in mind that I have not yet even applied to schools yet! I'm sure there are people on the board with more experience who have a different perspective. So,.....PV=nRT.
Good luck! - Doug