Background: The aim of the present randomized, double-blind, placebo-controlled study was to determine the efficacy of zinc sulfate on the duration and severity of common cold in children.
Methods: Children presenting at least two of 10 symptoms of common cold within the 24-48 h of the onset of illness were eligible for the study. Children were randomized to receive either oral zinc containing zinc sulfate or placebo. A diary was completed to record symptoms and adverse effects. Symptoms were scored as absent (0), mild (1), moderate (2), or severe (3).
Results: One hundred and fifty children participated in the study, and 120 children were included in the final analysis. The median duration of all cold symptoms was 6 days (P = 0.20), and the median duration of nasal symptoms was 5 days in both groups (P = 0.09). However, total symptom severity scores were significantly lower in the zinc group, starting from the second day of the study. The lower scores in the zinc group were largely due to improvement of nasal symptom scores. Adverse effects were similar in both groups.
Conclusion: Zinc sulfate had no effect on the duration of cold symptoms. However, it appears to be effective in reducing the severity of the cold symptoms in healthy children.