Null, Limited and Adverse Effects of non-Eby Designed Zinc Lozenges

Cold-Eeze® by Quigley

  • In 1992 Godfrey et al. first published the effect of lozenges containing zinc gluconate-glycine (1:10 mole ratio). The Cleveland Clinic followed with positive results of Cold-Eeze® in adults but later found no efficacy of Cold-Eeze® in children using a smaller dosage. Turner and Cetnarowski demonstrated Cold-Eeze® zinc gluconate glycine (ZGG) lozenges to shorten the median duration of laboratory-induced common colds compared to placebo by one day (3.5 to 2.5 days, a 28.6% reduction) as shown in their Figure 1A, but did not reduce symptom severity during the first 3 days. On the other hand, from their Figure 1B, neither reduction in median duration (5.5 to 6.0 days, a 8.3% increase), nor reduction in symptom severity was found when treating natural colds. Perhaps the reason for limited efficacy of Cold-Eeze® was published first by Eby in Chapter 4 of Handbook for Curing the Common Cold in 1994.

Halls® Zinc DefenseTM by Warner Lambert Company

  • Turner and Cetnarowski demonstrated total lack of efficacy of Halls® Zinc DefenseTM lozenges (see full document here) by Warner Lambert Co. in their November, 2000, Clinical Infectious Diseases article. These lozenges were zinc oleate/palmitate/stearate lozenges. Zinc acetate, fats and a highly acidic surfactant (PanodenTM) were used to produce Halls® Zinc DefenseTM lozenges. These ingredients with high heat converted in the candy cooking process to become hydrophobic compounds of zinc oleate, palmitate and stearate. See the Halls® Zinc Defense packaging demonstrating inclusion of these fats here. This composition was patented "to suppress the unpleasant mouthfeel (oral drying) of the functional ingredient (Zn2 ions)". In laboratory tests, these zinc compounds were non-ionizable, non-soluble and non-miscible (floated on water). These zinc wax-like compounds are not believed to be nutrients, not believed to be absorbed into the body, and are believed to be expelled only through the feces. Turner and Cetnarowski incorrectly omitted these fats from the list of ingredients in "Methods and Materials" in their year 2000 article. See this letter to the editor of Clinical Infectious Diseases "Elimination of Efficacy by Additives in Zinc Acetate Lozenges for Common Colds", dated May 15, 2001, or the PDF version (page 5 of 5). More on these fats. Inexplicably, Turner and Cetnarowski did not cite two previous reports of strongly positive results ( Petrus, et al. in 1998 and Prasad, et al. in 2000 ) of zinc acetate lozenges in reducing the duration and severity of common colds. Get Adobe Acrobat Reader.

Flavor-Masked Zinc Gluconate Lozenges

  • Pleasant tasting zinc gluconate lozenges flavor-masked with citric acid (not to be confused with citrus flavoring oils) release negatively charged species of zinc and worsened common colds. A major report was published in 1987 and is reviewed here. Commercial, pleasant tasting zinc citrate lozenges release negatively charged zinc species at physiologic pH 7.4 and are similarly believed likely to worsen colds.

All zinc citrate lozenges or zinc gluconate with citric acid lozenges have negative ZIA values and are believed to act as primary (T-cell lymphocyte) immunosuppressants. Their use in HIV patients or other immunosuppressed patients for a prolonged time could lead to serious sequela and possibly

  • Pleasant tasting zinc acetate or zinc gluconate lozenges with vitamin C (ascorbic acid) sound like a great combination. However, the ascorbic acid binds with zinc strongly at hard candy manufacturing temperatures and these lozenges are ineffective against colds. Interestingly, zinc ascorbate is non-miscible in water (floats on water). Zinc ascorbate is not a nutrient, is not absorbed into the body and it is expelled through the feces. Even so, these ineffective lozenges seem popular in Europe.
  • Pleasant tasting zinc gluconate lozenges with zinc oxide are likely to be mislabeled and are essentially zinc oxide. They release no Zn2+ ions and are ineffective.

Other Zinc Lozenges

  • Zinc orotate lozenges with zinc gluconate nasal sprays were completely ineffective in this 2006 report by Eby and Halcomb.
  • Pleasant tasting zinc lozenges containing zinc amino acid chelates can not shorten colds because the amino acid chelated zinc is too tightly bound to release Zn2+ ions at physiologic pH.
  • Pleasant tasting zinc oxide, zinc aspartate or "chelated zinc" lozenges can not shorten colds because they do not release Zn2+ ions at physiologic pH 7.4.
  • For a graphical look at which zinc compounds release Zn2+ ion, see this figure from authoritative sources.



For more information concerning the effects of electric charge on various common cold zinc treatments see the "Biologically Closed Electric Circuit".

For information related to where the rhinoviruses attack in the throat rather than the nose see the work of common cold experts Jack M. Gwaltney, M.D., and Frederick G. Hayden, MD, University of Virginia Medical School. Their article "How Cold Virus Infection Occurs" shows that rhinovirus attack starts in the throat which causes common cold symptoms. Their article "Anatomy of the Nose" shows that the nose transmits virus to the adenoids where infection starts.

The dry mouth test is a simple way to determine if a zinc lozenge will be effective. Zinc acetate lozenges always make the mouth feel dry (a clean mouth feeling identical to swishing out the mouth with water or tea for 30 to 60 seconds) - proving that the active ingredient, positively charged zinc ions, Zn2+ ions, are available. Dry mouth occurs because Zn2+ ions bind with and neutralize salivary proteins in the mouth. None of the ineffective copy-cat lozenges make the mouth feel dry and such absence shows that Zn2+ ions are not available.

Are you upset that those zinc lozenges you purchased this winter did nothing to help you get over your cold? Are you still sick and getting angry? We are upset too, and dismayed that many corporate store buyers have purchased ineffective copy-cat zinc lozenges rather than effective zinc acetate lozenges that have been proven effective in clinical trials.

Zinc Nasal Preparations Having Variable Efficacy

  • Zinc nasal preparations such as nasal sprays, nose drops and nasal packings soaked in zinc solutions were documented for use in treating common colds as early as 1901 and were indicated in more recent texts as being mild decongestants. Various compounds of zinc, both ionizable and non ionizable were common, but were abandoned about 1960 in favor of newer organic decongestants.
  • Ten millimolar zinc gluconate nasal sprays used every 15 to 30 minutes were tested in conjunction with neutrally charged zinc orate lozenges with null results for reduction in duration of colds, although severity of colds was reduced and decongestant action was apparent.
  • Figures presented by Derek Bryce Smith in his patent show that severity of some cold symptoms could be reduced by unchelated ionic zinc nasal sprays, but not their duration.


homepage - Zinc Acetate Lozenges for Common Colds