Zinc Lozenges, depending on the dosage and composition of the lozenges, may shorten the duration of common cold episodes by up to 40%, according to a study published in the Open Respiratory Medicine Journal. The issue remained to find out the precise amount to dose to achieve the most effective treatment.

To gain this trophy dosage amount, over a dozen of studies have been carried out to find out whether zinc lozenges are effective, but the results of those studies were inconclusive on the recommended dosage, namely Cocharane Collaboration.

Dr. Harri Hemila of the University of Helsinki, Finland, carried out a meta-analysis of all the placebo-controlled trials that have examined the effect of zinc lozenges on natural common cold infections.

Researchers compared 13 trials to identify effectiveness of Zinc lozenges. Of the 13, five with dosage less than 75mg had no effect on the cold. Dosage over 75mg reduced the cold up to 42%, trials using salts rather than zinc acetate with dose over 75mg decreased the duration of cold up to 20%.

In several studies, zinc lozenges caused adverse effects, such as bad taste, but there is no evidence that zinc lozenges might cause long term harm. Recent trial have found there were no significant differences between the zinc and the placebo groups in the occurrence of adverse effects although the daily dose of zinc was 92mg.

Dr. Hemila concluded that since a large portion of trial participants have remained without adverse effects, zinc lozenges might be useful for them as a treatment option for the common cold.

Published in The Open Respiratory Medicine Journal