since you only have like 10 posts either A, your a newbie to all this field, or B you just joined, whatever, if your a newbie and this is your first second or even third cycle, dont use slin, ya just dont need it, slin is something you use when steriods alone just arnt giving you enough gains and you want that extra, or you know what your doing but just wanted to ask, to answer your question yes you can use while on steriods, insulin works better when on steroids or HGH, but insulin will kill you, if you take to much anavar, not much will happen it just wont be absorbs, might messw/ you liver(300mg+crazy amounts), but if you did it once it really wouldnt fuck you up immediatlly, insulin, if you take to much, you WILL DIE RIGHT THERE ON THE SPOT, and if that doesnt scare you then it could make you VERY VERY FAT!! i like insulin i use it off cycle alot, but i almost slipped into Hypo-glycemia once, scared the shit out me, i didnt touch insulin for 4months afterthat , so just do your homework and be careful, more is not better with insulin, but dont go and eat 300grms of carbs when you take it to not go into hypo, if you eat insain amounts like that, thats kinda how you get fat.... you since your new should start at 2iu, work your way up 1iu ever time, untill you get to 8iu 10 maybe but no more than that, w/ that still you "should" only need 100grm of carbs to avoid hypo(10grm carb/1iu slin) carbo forces work well, but you should have and extra 150grams-200grams of sugars availible if you need them, i suggest you always take in 100grms of carbs after insulin no matter 1iu 0r 10iu, especially since you r new, but its not something to play around w/ it can and will kill you if your stupid... be careful, also this is one of the best insulin threads ive ever read, check it out,
http://elitefitness.com/forum/showthread.php?t=419355