Make sure that you have strong assessment skills. Inmates are chronic manipulators, and they will exaggerate and fabricate symptoms to get over on you - whether it is for medication, a doctor appointment or a trip to the hospital. Having worked with both males and females, generally speaking females seek medical attention earlier and for more minor reasons. The men tend to try to tough it out, and by the time they finally come in their problem is so far along that it takes some effort to get ahead of it. As with most things, the ideal path is somewhere in the middle.
Do not go anywhere with an inmate alone. Do not turn your back on an inmate when you are in a treatment setting. Deliver the best care that you can, but leave the "touchy feely" nursing that most of us were taught in school at the door. Terms of endearment and comforting touches are often misinterpreted by inmates as romantic interest, and they should be avoided. Remember that people aren't incarcerated for having good judgment. Stick to your policies. If you get a reasonable request and it doesn't violate regulations, there is nothing wrong with granting it. Deviating from policies is the road to compromise - something you want to avoid at all cost. Keep a close eye on sharps (needles, scissors, etc.).
Treat inmates with basic respect, but make it plain that they can't count on you to go around the rules. A big part of functioning in a correctional environment is how you interact with others. Be professional, maintain an appropriate professional distance from inmates, and follow written policies. If you do these three things, you will do fine.
I love corrections. I find it's very common to see nurses treat inmates differently than pts. on the outside. If you can resist the temptation to do that, you will do much better. Also, I don't like to know what they did before I treat them, if it was something really bad it makes it harder to be objective. The golden rule applies. As a matter of fact one of our "star nurses" was actually arrested for a domestic dispute (she didnt have to stay) and it happened years ago. What a shock when I saw her "mug shot" that someone showed me.