Ref (type)	Population	Outcome, Interventions	Results and statistical analysis	Effect size	Favours
Overall adverse effects
Systematic review	78 people with common cold Data from 1 RCT	Adverse effects 9/40 (23%) with zinc 3/38 (8%) with placebo	Significance not reported
Nasal stinging or burning
Systematic review	78 people with common cold Data from 1 RCT	Stinging or burning sensation 5/40 (13%) with intranasal zinc (daily dose 2.1 mg) 2/38 (5%) with placebo	Significance not reported