Zinc lozenges with certain chemical properties worked well in most tests, while others didn't work as often. This shows that how stable the zinc is might predict if it will work for you.

Different ingredients in zinc lozenges can change how well they work, even if the amount of zinc is the same, because some ingredients stick to the zinc and make it harder for your body to use it.

Different types of zinc lozenges release zinc in different amounts when they dissolve in your mouth, and this affects how well they work in studies.

Taking small amounts of zinc lozenges doesn't really help shorten a cold, but taking larger amounts might actually make you feel better faster.

When people take zinc lozenges soon after getting a cold, they usually don't have bad side effects and don't quit the treatment early in studies.