Randomized, double-masked, placebo-controlled clinical study of the effectiveness of zinc acetate lozenges on common cold symptoms in allergy-tested subjects.

This report of a randomized, double-masked, placebo-controlled clinical study demonstrates the effectiveness of zinc acetate lozenges on common cold symptoms in allergy-tested subjects. Subjects in the zinc and placebo groups were evenly matched with respect to sex, race/ethnicity, allergy test status, and age. Overall symptom duration was significantly less in the zinc group than in the placebo group (mean, 3.8 day vs 5.1 days). The mean severity rating for all symptoms was lower in the zinc group than in the placebo group; this difference, however, was not statistically significant. Allergy-positive subjects who used zinc had a statistically significant shorter duration of nasal symptoms than allergy-negative subjects (3.5 days vs 7.6 days). In conclusion, we propose that zinc acetate lozenges may significantly shorten the duration of common cold symptoms and relieve symptoms associated with allergies.