I have a number of classmates who were nurses before applying to medical school (plus many other allied health fields).seriously its easy. Just apply, don't stop yourself from applying based on what someone heard. I know RNs who say they like Doctors who've been in their position before. What does that tell you? Those MDs have been Nurses before.
I have no idea where this whole med schools don't take former nurses crap started....Sure, if you don't have a decent MCAT score or good grades you're less likely to get in, but really beyond that there is no anti-nursing sentiment from medical school faculty.