The common cold is a prevalent illness that is experienced at one time or another by the majority of the population. Cold symptoms can take a toll on both physical health and economic productivity. Zinc lozenges have been studied as a treatment method for shortening the duration of symptoms associated with the common cold.
The Common Cold
Symptoms of the common cold are attributed to a viral infection of the nose and throat. Although over a hundred virus types have been know to cause the common cold, the rhinovirus type is often the main culprit. Nasal symptoms include congestion, runny nose and sneezing. In addition, symptoms may include weakness, fatigue, headache, fever, cough and sore throat. Symptoms typically last between a few days to a couple of weeks.
In the laboratory, positively charged ionic zinc has been observed to have a number of antiviral effects. It has been proposed that zinc interferes with viral proliferation by inhibiting viral capsid formation when the virus replicates. Another theory is that zinc interferes with the binding and subsequent entry into cells by the virus. In addition, zinc may have positive effects in stimulating the immune system.
Zinc lozenges are designed to dissolve in the mouth. It is important not to chew or swallow the lozenges whole. Depending on the specific product, the lozenges may be used once every few hours up to a specified maximum daily dose. Patients should check the product labeling for complete directions and warnings before use. In theory, zinc lozenges release ionized zinc as they dissolve. The zinc concentrates in the throat area where it may interfere with viral replication and migration of the virus into other areas of the upper respiratory tract.
Although clinical studies in patients have yielded conflicting results, there is data to show that zinc may shorten the duration of colds. Published in the “Annals of Internal Medicine,” a 1996 study by Sherif B. Mossad and colleagues reported that complete resolution of cold symptoms occurred in 4.4 days in patients using zinc lozenges as compared to 7.6 days in patients using placebo. The results suggest that zinc lozenges may shorten the duration of the common cold. There is also evidence to suggest that lozenges that contain zinc acetate or zinc gluconate yield higher amounts of ionized zinc than other zinc complexes.
Although zinc lozenges are generally safe, caution should be used in children and persons at risk of choking. Zinc lozenges are usually only approved for use by persons age 12 and older. Patients should not exceed the recommended maximum amount on the product label. Patients should contact a physician if cold symptoms persist for more than 10 days.
- “Annals of Internal Medicine”; Zinc Gluconate Lozenges for Treating the Common Cold A Randomized, Double-Blind, Placebo-Controlled Study; Sherif B. Mossad, MD; Michael L. Macknin, MD; Sharon V. Medendorp, MPH; and Pamela Mason, BSN, MBA; July 1996
- American Family Physician: Zinc Acetate for the Treatment of the Common Cold
- “Medical Hypotheses”; Zinc Lozenges as Cure for the Common Cold--a Review and Hypothesis; Eby GA; Mar. 2010
- MayoClinic.com: Common Cold