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Zinc

By

Laura Shane-McWhorter

, PharmD, University of Utah College of Pharmacy

Last full review/revision Jan 2022| Content last modified Sep 2022
CLICK HERE FOR THE PROFESSIONAL VERSION

What is zinc?

What claims are made about zinc?

People most often take zinc in the form of lozenges to reduce the duration of cold symptoms. Some people take zinc to fight acne or improve heart health. Some people take zinc to slow the progression of age-related macular degeneration Age-Related Macular Degeneration (AMD or ARMD) Age-related macular degeneration (AMD) causes progressive damage to the macula, the central and most vital area of the retina, resulting in gradual loss of central vision. Central vision becomes... read more Age-Related Macular Degeneration (AMD or ARMD) , which is an eye disease, or to help heal wounds because zinc deficiency delays wound healing.

Mild zinc deficiency impairs growth in children and can be corrected with zinc supplementation.

Studies suggest that zinc supplementation helps people with prediabetes or diabetes control their blood sugar levels.

Does zinc work?

Scientific studies are inconsistent, but if zinc has an effect on the common cold, it probably is small and occurs only when it is taken very soon after cold symptoms develop.

Strong evidence indicates that zinc supplements, when combined with certain other supplements into a standardized preparation, slow progression of moderate to severe atrophic (dry form) age-related macular degeneration Age-Related Macular Degeneration (AMD or ARMD) Age-related macular degeneration (AMD) causes progressive damage to the macula, the central and most vital area of the retina, resulting in gradual loss of central vision. Central vision becomes... read more Age-Related Macular Degeneration (AMD or ARMD) . Evidence also shows that zinc may help people with diabetes and prediabetes control their blood sugar levels.

A 2016 study found that zinc supplementation may help relieve diarrhea in zinc-deficient or undernourished children (usually in low-resource countries) who are over 6 months old. There is evidence that, in low-resource countries, once-weekly supplements containing zinc and iron during the first year of life may decrease mortality due to diarrhea and respiratory infections.

What are the possible side effects of zinc?

  • Nausea

  • Vomiting

  • Diarrhea

  • Mouth irritation

  • Mouth sores

  • Metallic taste

  • Symptoms such as fever, coughing, headache, and fatigue

Because zinc is a trace metal and can remove other necessary metals from the body, intake of zinc lozenges should be limited (for example, to no more than 14 days). Zinc sprays may irritate the nose and throat and should be avoided.

What drug interactions occur with zinc?

The absorption and effectiveness of certain antibiotics in treating infection may be lowered if zinc supplements are taken at the same time; therefore, zinc should be taken at least 3 hours after these antibiotics.

Some drugs may decrease zinc levels. Examples include proton pump inhibitors such as omeprazole (which reduce the amount of stomach acid), the antihypertensive lisinopril (which brings blood pressure down by relaxing the blood vessels), corticosteroids, estrogens, and some antiseizure drugs.

Recommendations

Zinc supplements are not recommended for people in high-resource countries because most people in such countries get enough zinc through their diet without taking zinc supplements and taking too much zinc can lead to toxic levels with serious side effects. However, zinc supplements can decrease deaths due to common infections among children in low-resource countries.

It is not clear whether zinc supplements reduce the duration of common colds, but any such effect is unlikely to be anything more than minimal.

Zinc may also help control blood sugar levels in people with diabetes or prediabetes.

Drugs Mentioned In This Article

Generic Name Select Brand Names
PRILOSEC
PRINIVIL, ZESTRIL
PREMARIN
NOTE: This is the Consumer Version. DOCTORS: CLICK HERE FOR THE PROFESSIONAL VERSION
CLICK HERE FOR THE PROFESSIONAL VERSION
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