e200921c_sity_of_Michigan_Health_System__Why
[Supplement] 0 Stars Zinc Nasal Spray Not recommended due to a potenially serious side effect [Why] 
Zinc nasal sprays appear to be effective at shortening the duration of cold symptoms, however, some people have experienced long-lasting or permanent loss of smell after using the spray. Caution: Using zinc nasal spray has been reported to cause severe or complete loss of smell function. In some of those cases, the loss of smell was long-lasting or permanent.75 Zinc interferes with viral replication in test tubes.76 The beneficial effect of zinc nasal sprays should be weighed against the potentially serious side effect of loss of smell. Since zinc supplements are also effective and do not carry such a risk, it is more advisable to take zinc orally. A double-blind trial showed a 74% reduction in symptom duration in people using a zinc nasal spray four times daily, compared with the 42 to 53% reduction reported in trials using zinc gluconate or zinc acetate lozenges.77 The average duration of symptoms after the beginning of treatment was 2.3 days in the people receiving zinc, compared with 9.0 days in those receiving placebo. However, in another double-blind study, zinc nasal spray was no more effective than a placebo; in both groups the median duration of symptoms was seven days.78
Common Cold/Sore Throat (Holistic) | University of Michigan Health System
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