I have been an advocate of Zicam for a number of years now. I have sworn it reduces the duration of my colds, recommended it to my friends, and claimed I have never had a really nasty cold since I started using it.
It's entirely possible that it was all placebo effect--and that it was putting my health in jeopardy.
The FDA has asked the makers of Zicam to take their Zinc-containing products off the market while they investigate the significant reports that some consumers who have used the nasally-applied Zicam have permanently lost their senses of smell. Yeah, so... lots of water, Vitamin C, and rest for all future colds.