How much Vit C to give?

[eflat]

I have a non-vaxd 4yo and 18mo. 4yo has been coughing the last couple nights, with what sounds like an occasional 'whoop'. She had something similar 3-4 months ago. From looking at a few posts here, it sounds like giving vit c would be a good thing, but I didn't see much in terms of dosages for the different ages. Is there a guideline somewhere on dosages, and maybe type of Vit C to give?

TIA!

[Ophelia]

I'm sure there isn't anything 'official' but you can check this and then decide what you want to do:

http://www.mothering.com/community/forum/thread/1007979/possible-exposure-to-whooping-cough