There are two
well described (but often inappropriately interchangeable)
forms of silver toxicity. One is due to silver itself
and the second more severe complication is due to the attached
compound.
SILVER ION
TOXICITY
(Systemic)
Although
absorbed silver interacts with other metals and tissue
proteins, these interactions do not appear to be harmful
with the exception of the skin discoloration known as
ARGYRIA, a cosmetic problem.
Argyria is a
process of silver granule deposition in skin leading to a
permanent blue/gray discoloration There is no tissue
injury. The effect is a cosmetic problem. The most common
causes were not from medicinal use of silver but rather the
constant exposure to silver either as a chemist, silver
miner or long term use of silver cups, plates, etc. Of
interest is the fact that the term "blue blood"
used to describe Royalty came from the finding of mild
argyria in European nobility from the constant use of silver
place setting, silverware, and silver cups, leading to a
bluish skin color. Silver granules can be found in all
organs including the skin indicating that the silver
aggregates are not cleared. It would therefore appear that
any form of silver if given in large quantity can be a
causative factor. (at least 10 grams needs to be absorbed).
(Local)
Silver itself has been
shown to be harmless to normal human tissue. The
toxicity results from the salt or complexes which are
used to deliver the silver. A pure silver delivery would be
the ideal approach to avoid local toxicity.
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Silver
Sulfadiazine 1% cream
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Silver
Delivery (ACTICOAT)
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Silver
Nitrate 0.5% solution
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sulfadiazine can produce bone marrow suppression
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pro-inflammation response increasing surface
exudate
- impairing healing
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No
local toxicity reported
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nitrate causes oxidant damage
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toxic to fibroblasts; decreased healing
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can retard re-epithelialization
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propylene glycol toxicity
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chloride binding can lead to systematic hypochloremia
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allergic responses reported
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