This article is from the Fleas, Ticks, and Your Pet FAQ, by tittle@zmall.com (Cindy Tittle Moore) with numerous contributions by others.
Flea powders are handy, but there are many types and some are rather
poisonous. Check the poisonous list below for ingredients that cause
serious problems (for cats). When using powders, it is not enough to
just powder your pet: powder its bedding, and under furniture
cushions. You may want to add some to a discarded vacuum cleaner bag
especially if it will sit in the trash for a few days, but don't run a
vacuum with flea powder in the bag. That will probably spray it in the
air, potentially toxic to sensitive animals or humans.
Do not let your pet ingest flea powder of any sort. This can be tricky
with pets that groom themselves, such as cats and ferrets. With dogs,
if you brush the powder in, your dog will not ingest much if any
powder.
 
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