The most common parasites affecting ferrets are fleas, ear mites, coccidia, and heartworms. Few products are labeled to treat ferrets; however, if the dosage is adjusted for their size, products developed for other animals may be safely used in ferrets.
Pyrethrins, which are relatively safe even on baby kits, act as flea repellents and kill adult fleas. Products containing pyrethrins and similar ingredients, such as resmethrin are available in many forms including powders and sprays. Use a product that is labeled for use in ferrets, unless your veteriarian directs you to use a product 'off-label' An off-label product is one that is not licensed for use in a certain species or for a certain condition, but may be prescribed for such use by a veterinarian, such as Advantage.
Imidacloprid, the ingredient in Advantage blocks nerve transmission in adult fleas, immediately killing them. Advantage is available as a topical liquid that can be applied to the skin once a month. It then spreads to the rest of the animal's skin, and is resistant to the effects of water in the form of rain, swimming, or baths. It kills larvae as well as adults, so is able to bring a heavy infestation of fleas under control fairly quickly. It has no effect on the eggs in the environment, of course, and they will continue to hatch, so the flea problem is not solved until all eggs have hatched and the adults contact the pet and the Advantage. If used monthly, this treatment will probably also control ear mites. It is not labelled for use in ferrets, but to my knowledge, no adverse effects have been reported.
Lufenuron (pronounce loo-fen-your-on) is an insect developmental inhibitor. Its familiar trade name is Program® (Novartis). Program is available in an oral suspension for cats that may be used off-label, under direction by a veterinarian, to treat ferrets. Be aware that this product, like all other flea control products, is not labelled for ferrets. The manufacturer has no responsibility for any adverse effects that may result from treating animals other than those named on the label. To my knowledge, no reactions have been reported in treated ferrets.
Lufenuron is absorbed by the treated dog, cat, or ferret, and biting fleas get a dose of it with their blood meals. The eggs of treated fleas are damaged so that they do not hatch. This prevents the ordinarily rapid increase in numbers of young fleas in your house, but has no effect on the adults that are already there. The life span of an adult flea is at least a few months. If Program alone is used as flea control for animals that are already infested, it will take several months to eliminate all fleas from the house, because adult fleas are not affected. Program works best as a preventive, or in combination with other products that kill adult fleas on the animal and in the environment. Remember that all pets must be treated or there will be a constant source of fertile eggs hatching.
Precor and Nylar are insect growth inhibitors which can be found in products formulated for use on carpets and animal bedding. Some products are available which can be used directly on the animal and contain both a growth inhibitor and an insecticide. Growth inhibitors have no effect on people or pets, and they do not kill adult fleas, but they prevent the flea eggs from hatching and the larvae from pupating and turning into adults. Using the combination of a separate growth inhibitor with an insecticide that kills adults brings a flea problem under control very quickly compared to the old methods of bathing, dipping or spraying the pet, and using sprays, bombs, or powders in the house for several months. Best of all, the new chemicals are much safer for animals and people.
Ear mite remedies safe in cats are also safe in ferrets. These ear mite medications include trade names Mitaban (Pharmacia and Upjohn), Aurimite (Schering-Plough), and Cerumite (Evsco).
Heartworm preventives are often recommended for ferrets. Although no preventive has been specifically approved for use in ferrets, a veterinarian can choose to prescribe one for off-label use.
Trimethoprim sulfas, available in palatable oral suspensions for dogs and cats and humans, are easy to administer to ferrets with coccidiosis. Trade names of trimethoprim sulfas include Septra (Monarch), Bactrim (Roche), and many others. Dosage must continue for at least 10 days to control coccidiosis. Other oral sulfas may be used, but are very bitter and ferrets strongly resist treatment.