Common Cold - Zinc Lozenges reduced the duration of Common Cold Symptoms
Zinc Lozenges reduced the duration of Common Cold Symptoms
Reprinted with permission from ACp Journal Club
Mossad SB, Macknin ML, Medendorp SV, Mason p. Zinc gluconate lozenges for treating the common cold. A randomized, double-blind, placebo-controlled study. Ann Intern Med 1996 Jul 15; 125:81-88.
Objective: To determine whether zinc gluconate lozenges received during the first day of a cold are effective and safe for reducing common cold symptoms.
Design: Randomized, double-blind, placebo-controlled trial.
Setting: An outpatient department of a U.S. tertiary care hospital.
patients: 100 Cleveland Clinic staff members (mean age 38 y, 81% women, 76% white) who had cold symptoms for 24 hours, 2 symptoms (cough, headache, hoarseness, muscle ache, nasal drainage or congestion, scratchy or sore throat, or fever) and were not pregnant or immune deficient.
Intervention: 4.4-g, hard-candy lozenges that were composed of sucrose, corn syrup, glycine, lemon and lime oils, and either zinc gluconate trihydrate, 13.3 mg, or placebo. 50 adults were assigned to zinc lozenges and 50 to placebo lozenges. Lozenges were to be taken every 2 hours until symptoms were gone. Acetaminophen was allowed; other medications were discouraged.
Main Outcome Measures: Self-reported symptoms recorded daily for up to 18 days, amount of medication and lozenges used, and days to resolution of symptoms.
Main Results: Analysis was by intention to treat. The median time to resolution of all symptoms was 4.4 days in the zinc group compared with 7.6 days in the placebo group (p<0.001). The difference in time to resolution of all but 1 mild symptom showed similar results (3.7 vs 7.5 d, p<0.001). patients in the zinc group had fewer days with throat symptoms, coughing, headaches, hoarseness, nasal congestion, or nasal drainage (p0.04) for all comparisons). The groups did not differ for other cold symptoms or use of acetaminophen. More patients in the zinc group reported nausea (p=0.02) and found the taste of the lozenges to be unpleasant (p<0.001). The groups did not differ for other adverse effects (vomiting, abdominal pain, diarrhea, constipation, mouth irritation, or dry mouth).
Conclusion: zinc gluconate lozenges given to adults within 24 hours of the onset of cold symptoms reduced the duration of symptoms but tasted unpleasant and caused nausea.
Sources of Funding: Cleveland Clinic Foundation; Quigley Corporation (lozenges); McNeil (acetaminophen); Becton Dickinson (thermometers).
Reprints: Dr. M.L. Macknin, Department of pediatrics and Adolescent Medicine, A 120, Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, OH 44195, USA. Fax 216-444-0266.
Note: Commentary and Quiz Questions for this two-article set can be found at the end of the second article in the set.