I caught a cold visiting my sister in Colorado, so I raided her vitamin cabinet.
In addition to Echinacea root tincture (recall, Echinacea root is the only effective part; the aerial parts are bogus, because they do not contain the cold-fighting compounds), which I took, she had this Zicam oral mist, containing zinc.
The label said it was clinically proven to reduce the duration of a cold, something the FDA might take issue with. However, all I can say is I used it thrice daily, and this was the shortest duration cold I ever had. I wish I had had this stuff last year, when I had a cold that lasted from Halloween all the way to New Years. I am definitely investing in some when I get back to Wisconsin.
This is not a scientific case study of course, because, like I said, I also took Echinacea, as well as vitamins and a Mucinex type of thing. I also drank a lot of tea and got tons of sleep (I am on vacation after all...).
None the less, I feel like the Zicam spray did help shorten the duration of this cold, which is now almost gone. I don't know how I know, it is just a gut feeling.
Zinc has been shown to help fight colds. So, I'm not saying, I'm just saying...