Oral zinc may lessen common cold symptoms but adverse effects are common

Oral zinc treatments may shorten the duration of symptoms of the common cold in adults, although adverse effects are common, according to a study published in CMAJ (Canadian Medical Association Journal).

Canadian researchers looked at 17 with 2121 participants between 1 and 65 years of age to determine the efficacy and safety of zinc in treating the common cold. All trials were double-blinded and used placebos as well as oral zinc preparations. The authors found that, compared with placebos, zinc significantly reduced the duration of cold symptoms, although the quality of evidence was moderate. High doses of ionic zinc were more effective than lower doses at shortening the duration of cold symptoms.

"We found that orally administered zinc shortened the duration of ," writes Dr. Michelle Science, The Hospital for (SickKids), Toronto, with coauthors at McMaster University. "These findings, however, are tempered by significant and quality of evidence."

There was weak evidence that people taking zinc were less likely to have symptoms after one week, although there was no difference in symptoms between the two groups at three days. While zinc appeared to reduce the duration of symptoms in adults, there was no apparent effect in children. Participants taking zinc treatment were more likely to experience adverse effects including bad taste and nausea.

Previous studies have shown conflicting effects of zinc in reducing cold symptom severity and the duration of symptoms.

"Until further evidence becomes available, there is only a weak rationale for physicians to recommend zinc for the treatment of the common cold," conclude the authors. "The questionable benefits must be balanced against the potential adverse effects."

More information: www.cmaj.ca/lookup/doi/10.1503/cmaj.111990

add to favorites email to friend print save as pdf

Related Stories

Zinc lozenges may shorten common-cold duration

Jul 26, 2011

Depending on the total dosage of zinc and the composition of lozenges, zinc lozenges may shorten the duration of common cold episodes by up to 40%, according to a study published in the Open Respiratory Medicine Journal.

Zinc lozenges may shorten common cold duration

Aug 16, 2011

Depending on the total dosage of zinc and the composition of lozenges, zinc lozenges may shorten the duration of common cold episodes by up to 40%, says Dr. Harri Hemila from the University of Helsinki.

Zinc reduces the burden of the common cold

Feb 16, 2011

Zinc supplements reduce the severity and duration of illness caused by the common cold, according to a systematic review published in The Cochrane Library. The findings could help reduce the amount of time lost from work a ...

Zinc lozenges an ineffective treatment for colds

Aug 02, 2007

Despite 20 years of research, the benefits of zinc lozenges as a therapy for the common cold have not been proven. A new study, published in the Sept. 1 issue of Clinical Infectious Diseases, currently available online, review ...

Recommended for you

US approves new, hard-to-abuse hydrocodone pill (Update)

16 hours ago

U.S. government health regulators on Thursday approved the first hard-to-abuse version of the painkiller hydrocodone, offering an alternative to a similar medication that has been widely criticized for lacking ...

Soaring generic drug prices draw Senate scrutiny

20 hours ago

Some low-cost generic drugs that have helped restrain health care costs for decades are seeing unexpected price spikes of up to 8,000 percent, prompting a backlash from patients, pharmacists and now Washington ...

Only half of patients take their medications as prescribed

Nov 20, 2014

The cost of patients not taking their medications as prescribed can be substantial in terms of their health. Although a large amount of research evidence has tried to address this problem, there are no well-established ...

Interpol call for roadmap to tackle fake drugs

Nov 19, 2014

Interpol on Wednesday called for a greater global response to pharmaceutical crime as it warned criminal gangs were capitalising on weaknesses in legislation and border controls.

Empagliflozin in type 2 diabetes: Added benefit not proven

Nov 19, 2014

Empagliflozin (trade name Jardiance) has been approved since May 2014 for adults with type 2 diabetes mellitus in whom diet and exercise alone do not provide adequate glycaemic control. The German Institute for Quality and ...

User comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.