mate tell me about it, my persistent but untreatable ill health is the bane of my existance. so maybe im not the one to be giving out tips!
bare clementines/satsumas/oranges/fresh fruit juice (also excellent because all of the above are buff even when you feel buttters), supplemented by vitimin tablets and echinacea extract
as much sleep and rest as is possible
as few smoke and people filled clubs as possible
cos when you're ill, i think you're generally more vulnerable to other illnesses, so places where there are bare other people potentially carrying illness are a bad idea
if you just want to pretend you're not ill for a glorious 3 hours or so then paracetamol + codeine tablets are the bees knees, but dont drink too much with codeine! did so once while having wisdom teeth and i have never felt so horribly and uncontrollably fucked in all my life