I get a full panel done which includes a host of things. The bottom line is that AAS (depending ont he substance) can effect your liver, kidneys, & natural test levels (and other things).
I always get a full blood panel which hits lipid values, liver, kidneys, blood and testosterone. I've had thyroid issues in the past so I get that tested too.
I gotta tell you that I am happy as hell you are posting this too. Not too many people go out and do this - getting pre and post cycle blood work is very important. There was a post this past week about a guy who did AAS for years and NEVER got blood work done and now he is bitchin his health is fucked up.
Good luck!