Since there has been so much discussion lately about colloidal silver, I
would like to post for general information a veterinary advice column
devoted to the subject appearing in the new just-out issue of the
Independent Voice, written by Virginia ferret specialist Dr. Jean Wardell,
who has worked with Dr. Tom Kawasaki.
 
Q. There has been a lot of hype recently about the use of colloidal
silver as a cure for "the greenies." What is it?  Is it safe?  Does it
really work?
 
A. I have had several requests for information about this compound.  From
what I understand, it is being hailed as an apparent cure for epizootic
catarrhal enteritis or ECE, aka green virus diarrhea in ferrets.
 
A brief history and some background information about colloidal silver is
appropriate.  This compound was first introduced in the late 1800s as a
panacea with claims of being able to prevent and treat a variety of
maladies including tonsillitis and cancer.  Since it was first marketed
before 1938, it is treated as exempt from the FDA Act, which requires that
all drugs marketed after that year have concrete evidence attesting to
their safety and efficacy.  The only stipulations are that they be
advertised and labeled for the same uses as they were before 1938, and
that they be manufactured in the "original manner" (whatever that may be).
 
However, the FDA does not have any scientific evidence which supports the
claim of oral colloidal silver solutions being useful in preventing or
treating any serious disease conditions.  Furthermore, the FDA has not
approved a new drug application for colloidal silver.  In 1994, a number
of companies were issued warning letters for promoting the use of oral
colloidal silver as treatment for an unbelievable and extensive list of
health conditions that included HIV/AIDS, staph and strep infections,
diabetes, pneumonia, syphilis, and herpes.  These claims are fraudulent
and deceiving.  Products containing this compound are being used to treat
conditions that require a professional rather than lay-person diagnosis.
It is not possible for colloidal silver products to be used with a
guarantee of safety and efficacy.
 
Let's turn now to the question of the biological safety of such products.
Unfortunately, to date all the research, statistics, and studies have
been done on humans.  There is nothing available specifically addressing
the safety in animals.  The Office of OTC (over the counter) Drug
Evaluation has the results of a chemical assay report from the Dallas
Regional Pesticide Laboratory.  It was concluded that the amount of
silver present in the product was too low to result in toxicity in humans
at the recommended dose of one teaspoon per day.
 
The daily dose of oral colloidal silver currently being recommended by
some advocates is up to 2.5 cc per ferret.  Assuming the average adult
weighs 150 pounds and is taking 1 teaspoon per day, a 2-lb ferret would
require about .01 teaspoon or .05 cc.  A ferret receiving 2 cc of
colloidal silver would, using simple proportional arithmetic, be
ingesting about 40 times the recommended oral dose in humans.
[Moderator's note: Huh?  By my math 2.5cc in 150# human works out
closer to .03cc, not .05cc.  BIG]
 
It must be understood that over 90% of orally ingested silver is not
absorbed, and the liver's biliary system actively excretes it.  One of
the associated conditions of ECE in ferrets is hepatitis...  liver
inflammation disease.  This inherently implies that liver function is
reduced.  It may be theoretically possible for ferrets with ECE that are
treated with colloidal silver to develop toxicity due to their small size
and impaired ability to excrete the elemental silver.
 
Indiscriminate and improper use may also result in the development of a
condition known as argyria (which has been documented in people).  This
is an irreversible discoloration of the skin, conjunctiva, and internal
organs that occurs when silver salts are used over a period of time.
Unfortunately, the exact time frame which constitutes "a period" has not
been quantified.
 
I cringe when considering the potential effects, both short and long term,
that such products may have when administered to ferrets.  What is the
dose?  What is the frequency of administration?  In what form should it be
administered?  What are the side effects?  What are the implications in
ferrets that are already battling hepatitis secondary to the greenies?
These and other important questions remain unanswered.
 
As we are all well aware, ECE causes a constellation of clinical symptoms
in the ferret.  In the more severe cases, the typical green diarrhea is
accompanied by lethargy, depression, anorexia, weight loss, gastric ulcers,
hepatitis, and dehydration.  These are entities which need to be
individually addressed.  I worry about and do not advocate the use of
colloidal silver products in such a small, delicate species about which we
know very little to begin with...  to say nothing of how little we know
about the manner that some antiquated heavy metal-containing agent of
supposed therapeutic value affects them.  A veterinarian experienced with
ferrets should tailor the medical protocol of management for ferrets with
ECE.  Leave the silver for the jewelers and industrialists.
 
[Moderator's note: I'm trying hard to hold my tounge here - there's lots
to be said on both sides of the issue.  Comments welcome.  BIG]
[Posted in FML issue 1369]