Zinc Lozenges as a Common Cold Treatment
By George Eby
Email: george.eby “at” george-eby-research.com
Revision date: May 2, 2008
Purpose: Zinc lozenges
have only one basic use, that being a common cold treatment. The table
below is a review of commercial zinc lozenges sold in retail stores in the
This
article may be found on the Internet at:
http://Zinc-Lozenges.com . NOTE:
A Microsoft Document printable version is at http://Zinc-Lozenges.com/print.doc
Background: The only
biological effects of zinc are due to ionic zinc (iZn), which is available at
physiologic pH 7.4 only from a few zinc compounds, mainly zinc acetate and zinc
gluconate. The biological effects of
ionic zinc include antirhinoviral,
ICAM-1
inhibition, and interferon
induction and immune
system benefits. No other zinc
compounds release sufficient ionic zinc at physiologic pH 7.4 (pH of mouth and
nose) to have a beneficial effect as a common cold treatment. Response to the zinc lozenges is believed
completely dependent upon the zinc lozenge chemistry in the formulations and
dosages used and the time of zinc lozenge oral dissolution. The
lozenges must slowly dissolve over a 20 to 30 minute time period for efficacy
to be observed, because only the
ionic zinc absorbed into the oral tissues, which requires time, has any benefit
in treating colds. Swallowed zinc
has no effect on colds. Swallowing zinc
is not necessary for efficacy to result.
A perfect example of this requirement for “oral residence time” resulted
in two studies by the same Turkish researchers using zinc sulfate syrups and
later tablets to treat children’s colds.
The zinc sulfate syrups
(residing in the mouth for a while) were helpful but the (swallowed) tablets
were not. The chemistry of zinc lozenges
is very complicated (solution
equilibrium chemistry – a branch of inorganic biochemistry) and is well
beyond the training and scope of nearly all zinc lozenge manufacturers and
formulators. The interested
chemist/scientist/physician can learn something about this science by reading
"Zinc
Lozenges: Cold Cure or Candy” Solution
Chemistry Determinations”. Other
applicable data sources are found here. All of the zinc lozenges found on this page
are believed to provide nutritional support.
Zinc compounds
used in lozenges: Most zinc lozenges
are marketed as “zinc gluconate”, “zinc gluconate-glycine” or “zinc acetate”
lozenges, although there are several other types on the market. One would expect to receive “zinc gluconate”
when one purchases “zinc gluconate” lozenges, and “zinc acetate” when one buys
“zinc acetate” lozenges. However,
manufacturers nearly always add other ingredients, such as food acids
designated as “inactive” ingredients, usually to improve lozenge flavor or to
increase market appeal, for example by adding vitamin C (ascorbic acid), or
other ingredients. These “inactive”
ingredients are actually very “active” chemically and they react with the
highly ionizable zinc compounds used to produce other zinc compounds through
solid state reactions after the zinc lozenges are manufactured. These reactions continue from the date of
manufacturer until usage, and they may also occur in the saliva of people using
those zinc lozenges. These other
ingredients are necessary flavor masks in zinc gluconate lozenges since zinc
gluconate reacts with all carbohydrate sweeteners (except fructose) to form
very bitter compositions. Consequently,
the other ingredients act as flavor masks by converting the zinc gluconate to
another zinc compound that does not have the terribly bitter taste of zinc
gluconate. Citric acid, ascorbic acid
and glycine are the usual flavor masks; and glycine always diminishes or
eliminates iZn, while citric and ascorbic acid usually completely eliminate
ionic zinc (iZn), rendering the product useless. Zinc acetate lozenges are flavor stable and
pleasant tasting without added chemicals and provide a much better source of
ionic zinc, yet zinc acetate is relatively uncommon in zinc lozenges. The consequence of these added ingredients
are known to solution chemists (since they can calculate it based on libraries
of solution chemistry data, but these consequences are usually not known to
other scientists, manufacturers, formulators, physicians or the public.
What zinc
compounds release bioactive ionic zinc (iZn)? The mouth knows! Ionic zinc (the active ingredient) always
tastes astringent and orally drying and metallic. Lozenges containing substantial iZn do not
taste like candy! Analysis of zinc lozenge compositions using solution equilibrium
chemistry techniques produced the following amount of ionizable zinc (iZn - the active ingredient) at physiologic pH 7.4:
·
Zinc acetate yields 100% iZn.
·
Zinc gluconate yields 72% iZn.
·
Zinc gluconate-glycinate yields <57%
iZn.
·
Zinc gluconate + citric acid (or zinc
citrate) yields 0% iZn.
·
Zinc ascorbate yields 0% iZn
·
Zinc aspartate yields 0% iZn.
·
Zinc oxide yields 0% iZn.
NOTICE: Manufacturers may change their formulas
without notice, and the reader is recommended to check the list of “inactive”
ingredients and search for additives that may result in a change in zinc
lozenge chemistry (mainly food acids such as amino, citric and ascorbic acids,
as well as inactive zinc compounds like zinc oxide, zinc aspartate, zinc
citrate and zinc ascorbate). These data
in the table below are believed accurate and they use the best information
available, but without much more clinical data on efficacy, there remain
questions that must remain unanswered and there may be some incorrect
assumptions and expectations. None of
these products are recommended for serious diseases such as influenza.
Safety of zinc
lozenges: The use of large amounts
of zinc (as may occur with use of these zinc lozenges) for 7 days or less is not
believed to be harmful according to Dr. Ananda S. Prasad, MD, PhD, the
godfather of zinc biochemistry, and these large doses may result in other
observed benefits such as elimination of menstrual
cramping and bloating in women and elimination of angina
pectoris and Reynaud’s disease, showing important cardiovascular
benefits. However, extended use, (for
considerably longer than 1 week) is not recommended since reversible immune
system impairment may occur with extended use of high dose zinc. The
main side effect of large doses of zinc is nausea,
which may become sufficiently severe to cause prolonged vomiting, which is an
indication of zinc overdose. If overdose
occurs, immediately stop ingesting zinc.
Lack of safety
of intranasal zinc (nose drops, nasal sprays, nasal gels): This table does not include information on
zinc nose drops, zinc nasal sprays, or zinc nasal gels. Intranasal zinc has been known since 1938 to
carry a risk of anosmia (loss of the sense of smell). This means spraying ionic zinc into the nose
may result in contact of the zinc with the olfactory bulb which is in the top
of the nose, which will cause excruciating, unremitting pain and persistent anosmia
(loss of the sense of smell) which appears to be a permanent condition. Much more information is available here.
The
big table below: The following huge table presents the zinc lozenge
products found on the Internet and analyses them chemically from the list of
ingredients given by the manufacturer, and shows the author’s expert opinion of
what results he expects from use of those lozenges. George Eby’s expert status on zinc lozenges
and common cold treatment can be verified at the eTblast expert finder which uses the rank number of
academic/medical journal articles published to determine expertise. George Eby invented zinc lozenges as a cure
for common colds (U.S.
Patent # 5409905). There are no
active, basic patents on zinc lozenges as a common cold treatment
remaining. To see all of George Eby’s
medical journal articles, click here. To go to George Eby's home page (many natural
treatments for diseases) click here
and to go to his ColdCure website click here. The table below presents:
(1) the product (with a link to a sales site) / manufacturer,
(2) George Eby’s expert opinion of what results he expects and alternative
possibilities or suggestions for use,
(3) directions on zinc lozenge packaging and any alternative directions,
(4) the zinc compound listed on the label (with link to solution chemistry
computation of zinc compound used),
(5) the zinc compound expected after
reactions with “inactive” lozenge ingredients (with link to solution chemistry
computation of zinc compound expected), and milligrams of iZn (the active
ingredient) per lozenge,
(6) a link to the academic/medical journal article most nearly representing the
product from the perspective of the chemistry of the lozenge, and
(7) comments.
How listed? Zinc lozenges
are listed according to the amount of iZn
available from each zinc lozenge, which may or may not correlate with
efficacy. Be certain to check out the
least effective, because it may substantially increase the duration of colds.
For more information: Send email to: george.eby “at” george-eby-research.com
|
Attention distributors: The only contract
manufacturer having an FDA legal, dedicated production facility for
homeopathic 14 mg zinc lozenges (40 mg zinc acetate / 4 gram lozenge) as a
common cold treatment is Summa RX
Laboratories in Mineral Wells, Texas.
They made three of the successful clinical trial zinc lozenges (Eby
1984, Petrus
1998 , Prasad
2000 ) over the last 20 years.
They know how to do it right!
Why sell a useless product
with no iZn when you can sell 14 mg iZn lozenges with legal homeopathic drug
claims for as a common cold treatment, which shorten colds by 3 to 4
days? Why not contract with a company
that knows what they are doing? |
|
Product name Distributor |
Expected Results Against Common Colds |
Directions on Label |
Zinc compound claimed on label |
Zinc compound expected after reacting with other
lozenge ingredients & mg iZn |
Academic / medical research article most applicable
to product |
Comments “manufacturer’s comments” Eby comments
(without quotation marks) |
|
Eby’s ColdCure™
Zinc Acetate Lozenges Eby Pharma: Contact: George Eby Eby Pharma LLC Ph: 1-512-263-0805 george.eby “at” george-eby-research.com |
3 to 4 day reduction in
duration of common colds and reduction in severity of all common cold
symptoms when used as directed. If
used one-after-another (twice as frequent as recommended), reductions in
duration may reach 5 to 7 days. Benefits extend to reduction
in respiratory allergy symptoms, with lozenges providing benefits lasting 2
to 4 hours. |
START WITH 2 LOZENGES - ONE
AFTER ANOTHER - AT THE FIRST SIGN OF A COLD (A SCRATCHY THROAT). After first dose slowly allow one lozenge
to dissolve in the mouth every 2 hours with 1 before bedtime – maximum 10
lozenges / day [142 mg elemental zinc].
Don’t skip doses or stop taking doses until all common cold symptoms
have been absent for 6 hours. |
Zincum aceticum 2X (zinc acetate) (14 mg zinc) |
Zincum aceticum 2X (zinc acetate) 14 mg iZn |
Eby’s ColdCure™
Lozenges are slightly stronger (14 mg iZn) than the lozenges tested by Prasad
(12.8 and 13.3 mg iZn) and substantially stronger than the 9 mg iZn lozenges
tested by Petrus. |
“These are pleasant
peppermint flavored lozenges, but are astringent, drying and metallic
tasting, which is representative of iZn.” These are the strongest
compressed tablet, pleasant tasting zinc lozenges available. They are labeled and marketed as a
homeopathic common cold treatment. |
|
Fast Dry™ Zinc Lozenges By F&F Foods: Distributors contact: Dave
Barnett, President F&F Foods Ph: 1-773-927-3737
extension 695 Fax 1-773-927-3906 1-630-235-7890 dbar “at” fffoods.com |
3 to 4 day reduction in
duration of common colds and reduction in severity of all common cold
symptoms when used as directed. If
used one-after-another (twice as frequent as recommended), reductions in
duration may reach 5 to 7 days. Benefits extend to
reduction in respiratory allergy symptoms, with each lozenge providing
benefits lasting 2 to 4 hours. |
START WITH 2 LOZENGES - ONE
AFTER ANOTHER - AT THE FIRST SIGN OF A COLD (A SCRATCHY THROAT). After first dose slowly allow one lozenge
to dissolve in the mouth every 2 hours (not every 3 hours), with 1 before
bedtime – maximum 10 lozenges / day [142 mg elemental zinc]. Don’t skip doses or stop taking doses until
all common cold symptoms have been absent for 6 hours. |
Zincum aceticum 2X (zinc acetate) (14 mg zinc) |
Zincum aceticum 2X (zinc acetate) 14 mg iZn |
Fast Dry™ Lozenges are slightly
stronger (14 mg iZn) than the lozenges tested by Prasad (12.8 and 13.3 mg
iZn) and substantially stronger than the 9 mg zinc lozenges tested by
Petrus. F&F Foods made the 13.3 mg
zinc acetate lozenges tested by Prasad in 2008. |
These are pleasant cherry
flavored hard candy (not compressed) lozenges, but are astringent, drying and
metallic tasting, which is representative of iZn. These are the only
effective hard candy zinc lozenges available. Homeopathic common cold
treatment. |
|
by Auriga Laboratories |
3 to 4 day reduction in
duration of common colds and reduction in severity of all common cold
symptoms when used as directed. If used
one-after-another (twice as frequent as recommended), reductions in duration
may reach 5 to 7 days. Its benefits extend to
reduction in respiratory allergy symptoms, with each lozenge providing
benefits lasting for 2 to 4 hours in allergy treatment. |
START THERAPY WITH 2
LOZENGES, ONE AFTER ANOTHER, AT THE FIRST SIGN OF A COLD (A SCRATCHY
THROAT). After initial dose slowly
dissolve one lozenge in mouth every two hours, with one before bedtime –
maximum 10 lozenges / day [142 mg elemental zinc]. Do not skip doses or stop taking doses
until common cold symptoms have been absent for 6 hours. |
Zincum aceticum 2X (zinc acetate) (14 mg zinc) |
Zincum aceticum 2X (zinc acetate) 14 mg iZn |
Zinx®Lozenges are slightly stronger (14 mg iZn) than the lozenges
tested by Prasad (12.8 and 13.3 mg iZn) and substantially stronger than the 9
mg lozenges tested by Petrus. They are
most like the 13.3 mg zinc acetate lozenges tested by Prasad in 2008. |
These are pleasant
peppermint flavored lozenges, but are astringent, drying and metallic tasting,
which is representative of iZn. These are the strongest
compressed tablet, pleasant tasting zinc lozenges available. They are labeled and marketed as a
homeopathic common cold treatment Homeopathic common cold
treatment. |
|
By Matrixx
Initiatives. |
One day reduction in
duration with reduction in symptom severity when used as directed. If patients hold zinc
laden saliva in mouth for 30 minutes or longer each use, reductions in
duration of 3 to 5 days may result. Its benefits are likely to
extend to reduction in respiratory allergy symptoms, with each lozenge providing
benefits in allergy treatment lasting for 2 to 4 hours. |
Dissolve entire tablet in
mouth. Do not chew. Do not swallow whole.
Take one tablet at the onset of symptoms. Repeat every three hours until symptoms are
gone. For best results, use for an additional 48 hours after symptoms
subside. Do not eat or drink 15
minutes after use. Do not eat or drink citrus fruits or juices for 30 minutes
before or after. Otherwise, drink plenty of fluids. Homeopathic treatment for
common colds |
Zincum Aceticum, (zinc acetate) Zincum Gluconicum (Zinc Gluconate) (13.3 mg zinc) |
Zincum Aceticum, (zinc acetate) Zincum Gluconicum (Zinc Gluconate) 10.4 mg iZn |
None. Clinical trials are needed
to support manufacturer claims of efficacy in reducing the duration and
severity of common colds. |
Tablet dissolves too fast
for significant oral absorption of ionic zinc to have major impact on
duration of colds. Nearly all is
swallowed. Reasonably pleasant zinc
gluconate taste and zinc aftertaste. The longer the zinc laden
saliva is held in mouth, the better the results will be. To avoid minor stomach upset, do not take
on an empty stomach. |
|
by Quigley |
One to two days reduction
in duration and reduction in symptoms severity. Its benefits are
likely to extend to reduction in respiratory allergy symptoms, with each
lozenge providing benefits in allergy treatment lasting for 2 to 4
hours. |
For maximum effectiveness
start taking lozenges at the first sign of a cold. Best within 48 hours.
Completely dissolve a lozenge in mouth. Do not chew. Repeat every 2 to 4
hours as needed. Recommended daily dose of
lozenges is 6 drops per day. Homeopathic common cold
treatment |
(13.3 mg zinc) |
7.6 mg iZn |
Godfrey
1992 (original ZGG trial) Macknin
1998 (Children’s Cold Eeze®) McElroy
2003 (Children’s Cold Eeze®) This is the most tested
zinc lozenge product, and it is the market leader. There are no indications of harmfulness in
any of the published medical literature reviewed. |
The 3 to 4 day reduction in
duration and “42% reduction” claimed are believed overstated. There has been wide variation in clinical
trial results of Cold-Eeze, with results ranging from a half day increase
in duration to 3 days reduction in duration as shown in this 2004 report. There are a variety of Cold-Eeze® products,
and some have not been clinically tested. |
|
By Olympian Labs Products |
No benefit expected. |
Zinc lozenges are most
effective if taken at the first sign of symptoms, ideally within 24 hours.
Then it is recommended that a lozenge be taken every two hours while awake
for maximal efficacy. |
(1 mg zinc) |
0.72 mg iZn |
None. There are no clinical trials in support of
this product. |
“Zinc Lozenges may help you
through tough cold seasons as well as relieve symptoms from allergies. Zinc has been shown to reduce the average
duration of colds and reduce the severity of cold symptoms.” |
|
By Hyland’s |
No benefit expected. |
Adults: Dissolve 2 to 3
tablets under tongue every 4 hours or as needed. Children 6 to 12 years: 1/2
adult dose. Homeopathic. 100% Natural, no side effects. Soft tablets dissolve
instantly. This all natural homeopathic formula works without side effects
and won't interact with other medications-day or night. |
(0.24 mg zinc) |
0.18 mg iZn |
None. There are no clinical trials in support of
this product. |
Active Ingredients:
Aconitum Napellus 6x HPUS, Allium
Cepa 6x HPUS, Zinc Gluconate 6X HPUS, Gelsemium Sempervirens 6X HPUS. “Hyland's Cold Tablets with
Zinc Quick dissolving tablets provide fast natural relief from symptoms of
the common cold.” |
|
By SmartScience Laboratories, Inc. |
Symptomatic relief starting
in the first day of treatment, but no reduction in duration of common cold
symptoms. |
Begin at first sign of
cold. Dissolve lozenge in mouth. Repeat in 30 minutes and each 3 hours. Up to 5 lozenges per day. Homeopathic common cold
treatment |
(13.1 mg zinc) |
0 mg iZn |
The only difference between
the product Turner studied and this product is the addition of citric acid as
a flavor mask, which eliminates all iZn.
There should be no differences in results. |
The symptomatic relief is
believed produced by troxerutin, one of the inactive ingredients. “There is NO unpleasant
metallic aftertaste like that experienced when taking many of the other zinc
cold remedies.” |
|
By Halls |
No benefit expected No common cold claims are
made by the manufacturer. |
As a dietary supplement for
adults, take 1 drop 4 times per day. |
Zinc sulfate |
Zinc citrate Zinc ascorbate 0 mg iZn |
None. There are no clinical trials in support of
this product. |
Do not use for more than 8
weeks consecutively. Do not use if you have a severe systemic illness. Do not
use if you have allergies to the daisy family (Asteraceae).
Do not use if you are pregnant or breast feeding. |
|
by GNC |
No benefit expected No common cold claims are
made by the manufacturer. |
As a dietary supplement,
take two to six lozenges daily, preferably after a meal. Allow the lozenge to
dissolve slowly in the mouth. Do not chew. |
Zinc oxide (20 mg zinc) |
Zinc oxide 0 mg iZn |
None. There are no clinical trials in support of
this product. |
Zinc oxide is only slightly
soluble in water, and is essentially non-ionizable and does not release zinc
ions (iZn) sufficient to have an effect on common colds or rhinoviruses. |
|
By Puritan’s Pride |
No benefit expected when used
once or twice daily as recommended.
May lengthen colds by one day if used too frequently. |
Dissolve one lozenge in
mouth one or two times daily. Do not exceed two per day. |
Zinc citrate and
Zinc Gluconate (23 mg zinc) |
Zinc citrate and
zinc
gluconate-citrate |
These lozenges should taste
like candy and function like candy. |
|
|
By Arrowroot |
No benefit expected. No common cold claims are
made by the manufacturer. |
Not observed |
23mg zinc 100mg of vitamin C |
Zinc ascorbate 0 mg iZn |
None. There are no clinical
trials in support of this product. |
“Minerals, like vitamins,
help our body systems function. They support the proper utilization of
vitamins as well as the building of blood, bones and teeth. Minerals also
control muscle tone and the maintenance of healthy nerves. |
|
by Amerifit. |
No benefit expected, although
colds might be slightly worsened and might last a half day longer. |
Take 1 lozenge every 3-4
hours. Allow lozenge to dissolve in your mouth. |
Zinc Liposome; Zinc citrate (10 mg zinc) |
0 mg iZn |
“THIS PRODUCT IS NOT INTENDED
TO DIAGNOSE, TREAT, CURE, OR PREVENT ANY DISEASE.” |
|
|
By Progressive labs and by Kordial Nutrients |
No benefit expected. |
As a dietary supplement,
two (2) lozenges daily, or as directed by a healthcare practitioner. For
short term high-intensity use, one or two (1-2) lozenges every two to four
(2-4) hours, dissolving completely in the mouth. Do not exceed 10 lozenges
per day or use intense levels for more than 7 days. |
(24 mg zinc) Plus 300 mg ascorbic acid |
Zinc ascorbate 0 mg iZn |
None. There are no clinical
trials in support of this product. |
“Zinc in lozenge form
provides enough zinc to nasal tissues to be effective against the common
cold.” Zinc gluconate plus
ascorbic acid yields insoluble zinc ascorbate in solid state reactions. |
|
By |
No benefit expected. |
As a dietary supplement,
adults take One (1) lozenge every Two (2) hours while awake, or as directed
by physician. Allow to dissolve completely in the mouth. Do not exceed Ten
(10) per day. Children over the age of Four (4) years may use half the adult
dose. |
Zinc glycinate (10 mg zinc) |
Zinc glycinate 0 mg iZn |
None. There are no clinical trials
in support of this product. |
“Numerous studies support
the fundamental role of zinc in normal immune response in humans. Immune
cells must be able to rapidly divide in order to respond to daily challenges.
Like all rapidly dividing cells, immune cells depend on adequate amounts of
dietary zinc.” |
|
Zinc Lozenges with Cherry
Flavor by Basic Organics |
No benefit expected, although
colds might be slightly worsened and might last a day longer. |
At first sign of cold
symptom, take 2 Zinc lozenges.
Dissolve in mouth slowly & completely. Thereafter take 1 Lozenge
every 2 hours while awake. |
(10mg zinc) Zinc Gluconate Citric acid |
Zinc citrate and
zinc ascorbate 0 mg iZn |
This product carries mixed
signals, with advertisement reading to “start at first sign of a cold
symptoms” yet it is marketed as a
“100% natural dietary supplement with zinc.” |
|
|
By DaVinci
Laboratories |
No benefit expected. No common cold claims made. |
Take 1 lozenge in AM and 1 lozenge
in PM. Let dissolve in mouth. |
Citric acid |
0 mg iZn |
Zinc lozenges are a great
tasting lemon flavored supplement for both children and adults. |
|
|
By Zand® |
No benefit expected. No common cold claims made. |
Allow lozenge to slowly dissolve
in the mouth. May be repeated as needed. |
(5 mg) |
0 mg iZn |
“Sweetened Only With
Natural Rice Syrup.” |
|
|
By Nature’s sunshine |
No benefit expected. |
