I god idea if you write, draw, have a comic or what ever, is to read it all over, it helps to see why did you started and how far have you gone, I allways burn out, I got really a short fuse. so when I get blocked in short term, I go walk, drink a lot of water (Sometime is just dehydration), take a nap, or something that doesn't has to do with computer (Because I usually work on computers). And if is a long term, maybe give me a break, go to my parents place for a weekend, or go out with friends. I just get out of a long term block that get me even depresed, so if its to hardcore, I really don't know what to do, it'll pass. Also, you can't force you to work in creative if you're burnout, It won't help, It will make things worts.
PD: Sorry if it doesn't make any sence