Excessive zinc intake (doses of 50 mg or more per day) can cause nausea, stomach pain, vomiting, dizziness, headaches, and ...

There is no agreed-upon dose when taking zinc for a cold, but doses between 50 to 180 mg for one to two weeks are generally well tolerated, Prest continues. “Some research suggests that the best ...

When taken by mouth: Zinc is likely safe when used in amounts no greater than 40 mg daily. It is possibly safe when taken in larger doses, especially when used only for a short period of time.