Can I apply for new job while on sick??

Hi,
I took time off work (its been over a year now!) because i was due head surgery, and needed time to recover and everything. So this was in October, the surgery happened. And since then i've just been sitting about house, wanting to DO something, it's so boring being stood inside day in/out not doing anything, and no one to talk to anymore Not to mention your not getting any income, my sick pay stopped along time ago now because u only get so much time till sick pay stops. So what i'm living on now is just benefits. So i thought about applying for jobs whilst i'm off (coz i REALLLLLLYY hate my job aswell, its the shift times i hate mostly, and the location). But i was just wondering, are you able to apply for jobs whilst on sick?? Because you have to put refrences names down aswell, which would be your employers, and they all think 'your on sick leave why u applying for jobs?' So i'm just thinking what do i do!! Is it best to just quit the job, but then u dont know if your going to get another job etc. Should i wait till my Doctors say everything bk to normal and then quit job/apply for jobs?? I really just need employment advice.