Why zinc? Zinc has been in and out of favour as a treatment for the common cold, based on findings, since the first randomised trial was published in 1984.

A 1998 systematic review (which did not include a quantitative synthesis of data) suggested that zinc was beneficial in reducing the duration and severity of cold and viral symptoms.4 A meta-analysis published in 2000 found that zinc was ineffective compared with placebo in reducing the likelihood that cold symptoms were present after 7 days. A meta-analysis published in June 2011 concluded that zinc lozenges reduce the duration of cold and viral symptoms by 12% to 48%, but only at daily doses >75 mg.

Dose during infection ;One, three times a day 

Maintenance dose; One per day