I am taking zinc but take it with a meal so it doesn't make me sick. I haven't taken Moly B at the same time. When I was taking it I was taking it alone. I relized yesterday it may be that I am allergic to Sulfa and that is why Moly B doesn't agree with me. MSM gives me hives after a couple of weeks on it. They say it's not supposed too if your allergice to sulfa but it does with me.