How many cups of orange juice a day when sick? also, i get nosebleeds when i blow my nose why is that and how can i prevent it?

You have a cold?: The idea that taking megadoses of vitamin C for a cold has been shown to be wishful thinking. So have as much or as little OJ as you please. Regarding the nosebleeds, during an upper respiratory infection, the nasal mucosal tissue may become very friable, or delicate, with rich vasculature susceptible to bleeding. Use Vaseline or saline spray intranasally to keep moist and see your doc if needed!