Do you take airborne or similar product when you start feeling sick?

I am doing this poll becuase I saw that some members were getting sick before their races and was wondering if they try using these products! About three weeks before my race I got sick and started taking airborne, the cold only lasted a few days.  A week before the race it tried to come back and I started taking the airborne every three hours as stated on the package and never got sick!

I've used Zicam several times in the past year.  I've taken it when I start feeling sick and this is the first year I can remember when I haven't been down with anything very serious.  My whole family was sick starting two weeks before my HIM and I felt it a bit the week before, but started poping the Zicam and it went away quickly. 

Of course, I can't say it was all the Zicam, but it's an interesting coincidence.  I asked a pharmacist about whether it did any good, and he said that the reason it 'might' help is that it bonds to the places where the germs normally would or something like that.  (That's filtered through my non-medical mind, so cut me a little slack!) 

Any docs care to comment on this stuff?  Is it worthwhile, why might it work or not?