I've used zinc for the last few months. I've read a lot of reports of people saying that they have gotten clear in just a few days. Even though I don't say that their statements aren't true, it has not worked for me that way. I saw results after a few weeks of using zinc. As far as I've been told, it will take new spots a month before they come up. So it is natural for zinc not to clear you in just a few days, as any acne treatment for that matter.
I did try taking zinc before and usually I quit after a week or so, not seeing results and the zinc making me nauseous. For all those people that are experiencing the same, hang in there for just a few more weeks. My acne has gotten a whole lot better, especially on my back. I've noticed that the oiliness in my face is also greatly reduced. It has given me other benefits as well, helping my eczema and dandruff, and I've noticed an increased libido.
The one thing I don't like about zinc is that is makes me nauseous every time, even a little bit if I take it with food. But for me, the benefits outweigh the nausea.
I began taking 60 mg of Now Foods L-Optizinc (30 mg in the morning and 30mg in the evening), and after a few weeks I've lowered the dose to 30 mg, which is fine. I've tried other types of zinc in the past but they didn't seem to work as well as the Optizinc one. The cheapest I've found so far is on iHerb, the code UPU014 gives you a 5 dollar discount.