Karri,
You asked about Program and Advantage.  Here's what I know about them.
 
Both products have been officially tested and approved for dogs and cats.
 
However, they have also been "unofficially" tried on ferrets, and the
"unofficial" consensus is that they are both fine for ferrets.  They are
both available only by prescription from your vet, who needs to see your pet
first (weight, general health, etc.) before prescribing.  The vet will ask
you to sign a release form first, because the products have not been
officially approved for ferrets.
 
Advantage is a wonderful product.  For ferrets, the cat/kitten (under 9 lbs)
version is used.  It comes in tube form; one package contains four tubes.
Once a month, you apply the solution (one tube) directly to skin near the
base of the animal's head.  Then let it dry-- don't let the fert carpet-shark
it off by rubbing around on the rug.  Twenty-four hours later, all the fleas
(98--100%) on your pet will be dead.  Your pet can't really reach back there
to lick it off, so it's perfect for ferts like mine who have a difficult
time with all-over flea products.  It's water-soluble, so you shouldn't
bathe your fert UNLESS it's done between applications, and the pet must be
completely dry before the next dose is applied.  As you can see, it works
pretty fast; the idea is to kill the fleas before they can lay their eggs .
 
Program (lufenuron) is also administered once a month.  It comes in either
liquid form (cats) or pill form (dogs).  As in the case of Advantage, the
dose is based on weight, so you would use the version for animals under ten
pounds-- either liquid or pill.  One package contains six treatments (taken
orally).  We use the pill form, crush it up in a mortar, and administer it
mixed in Ferretvite.  You need to be careful and not lose any of the crumbs
or powder-- the animal needs to take the entire amount.  You can dillute the
Ferretvite with a little Petromalt if necessary; we give it as a blob on the
hand, and let her lick it off.  Program doesn't produce perceptible results
until four weeks or more have passed.  It does not kill adult fleas, but
chemically disrupts the flea's reproductive cycle so that the flea can't
produce viable eggs.  As you can see, the fleas must first BITE your pet in
order for Program to affect them-- it is a long-term approach-- so you have
to use it in conjunction with another flea product (as long as fleas are
present in your home) which kills the adult fleas.  Also, all other pets in
the household must be on Program, too, in order to completely destroy the
next generation of fleas.  You will need to keep using it even after the
life cycle of your household fleas has been stopped, since it is always
possible to re-infest your home with hitch-hiking fleas on your clothes from
outdoors/other people's pets.
 
I really don't know much about Frontline, but I'm under the impression that
it is similar to Advantage, only each dose lasts MUCH longer and the product
is NOT water-soluble.  I suppose that could be either a potential minus or a
plus, depending on the individual situation.  I'm a little nervous about
anything that I couldn't wash off my little one if I needed to.
 
We recently found out (the hard way) that our Weezie is allergic to fleas.
She also seemed to be having some reactions to the other flea products (we
aren't sure about this).  Advantage solved all our problems.  I'm really,
really pleased with it.  One package costs about thirty bucks, and boy is it
worth every penny.  Weezie is approaching her third month on Program and her
second month on Advantage (we have her on both concurrently).  Since she's
been on Advantage, I've found fleas on her once, the other day (three
fleas).  Haven't found any since, so it may have been a freak occurence or
maybe they were mutant Rambo fleas.  I still flea-comb her to check her for
them, but now I am using a DRY comb (important!) so as not to get her neck
damp.  We plan to keep her on Program year-round, and slack off on the
Advantage during the cold months, as long as the fleas have disappeared.
 
Isabel Two and
Tristan's Lady (Weezie)
 
"So... you like your exotic dogs, Miss Fincannon?"
"Very much, Mr. Ludlow."
**********************************************************
 
[Moderator's note: I'd like to add a few comments to "Isabel Two"'s
informative post:
 
- Program is more effective if taken with food.  The more food the better.
- Neither Advantage nor Frontline require a perscription, but it is the the
  manufacturers' policy to sell only to veterinarians.  They were given
  approval as pesticides, not as drugs since neither is actually absorbed
  into the animals' body.
- More and more vets do seem to like having their clients sign disclaimers
  though I find it at least a little bit amusing since there are *NO* drugs
  approved for ferrets (2 vaccines are approved).  I mean, do you sign a
  disclaimer to get something like an antibiotic?   BIG]
[Posted in FML issue 1727]