Zinc for Colds: Lozenges and Nasal Sprays

You're stuffed up and sneezy and want some relief. If you could even make your cold just a little shorter, you'd be happy. Can zinc make a difference?

Maybe yes, maybe no. There are a lot of uncertainties about zinc's role as a cold buster.

What Is Zinc?

Zinc is an essential mineral that's found in almost every cell, and it helps your body resist infection. It also plays an important part in tissue repair. And it may lower the ability of cold viruses to grow on or bind to the lining of your nose.

You can buy zinc as supplement, but it's also found naturally in a number of foods, like:

  • Shellfish
  • Beef and other red meats
  • Nuts and seeds
  • Beans
  • Milk and cheese

Tea, coffee, and some medicines interfere with the way zinc is absorbed in your intestines.

Does It Work as a Cold Remedy?

Researchers report mixed results. One analysis reviewed 15 earlier studies and found that taking zinc through the first few days of a cold, either as a syrup or lozenge, may shorten how long you're sick.

It also appeared to prevent colds in people who used it over the course of about 5 months.

But in other studies, researchers found no differences in symptoms between those who took zinc and those who took a "dummy" pill.

What does this research mean to you and your family? For now, the studies are inconclusive. For every one that shows a benefit with zinc, there's another that finds it doesn't help at all. Many experts say that if there is any advantage in taking zinc, it's minor.

Is It Safe?

Short-term use -- less than 5 days -- doesn't cause serious side effects, but it can make your mouth irritated, leave a metallic taste, or give you an upset stomach.

Experts recommend that you not take zinc for more than 5 days. Long-term use -- more than 6 weeks -- can lead to copper deficiency.

Researchers say zinc nasal sprays cause animals to lose their sense of smell. There have been several reports of people having decreased sense of smell or completely losing it. Because of this risk, the FDA issued a warning to stop using several nasal sprays that contain zinc.

Keep in mind that zinc is necessary for your health and safe to take through food such as seafood and eggs. But supplementing with higher doses, particularly for a long time, can be toxic.


What’s the Bottom Line on Zinc and Colds?

While some studies show some help for colds from zinc lozenges and nasal sprays, the results are inconsistent. More research is needed. Zinc's side effects, especially when nasal sprays or gels are used, may outweigh benefits, which may be slight, at best.

WebMD Medical Reference Reviewed by David Kiefer, MD on January 24, 2015



Singh, M. Cochrane Database of Systematic Reviews, 2011.

NIH Office of Dietary Supplements: "Zinc."

American Family Physicians: "Treatment of the Common Cold."

Scientific American: "No proof zinc lozenges help cold symptoms."

US Pharmacist: "Zinc and the Common Cold: What Pharmacists Need to Know."

Medscape: "Efficacy of Zinc Lozenges Against Common Cold Viruses."

Oregon State University, Micronutrient Information Center: "Zinc."

Caruso, T. Clinical Infectious Diseases, Sept. 1, 2007.

Kurugöl, Z. Acta Paediatrica, October 2006.

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