Yeast.
Brewer’s yeast for fleas is considered effective because it contains thiamin. The smell and taste of thiamine are thought to be repellent to fleas, so when dogs and cats eat brewer’s yeast, fleas are repelled by the presence of thiamine in the skin or blood of dogs and cats. Thiamine is part of the group of B vitamins.
Getting rid of fleas with brewer’s yeast is easy to do, as yeast is readily available from supermarkets, health food stores, and online sources. It can be purchased in powder, liquid, or flake form. The most practical choice when using brewer’s yeast is its powdered form. For natural flea control, the powder can be mixed with food, spread on the animal’s fur, or dissolved in water.
A solution of 0.25 cups of yeast in 1 liter of water can be placed in a spray bottle and sprayed on a pet’s fur.
Brewer’s yeast for fleas should be dosed at 1 teaspoon (4.9 ml) for small dogs or cats. Medium dogs should get 2 teaspoons (10 ml) and larger dogs should get 1 tablespoon (14.8 ml). The yeast can be spread on dog or cat food, or used directly on pet fur as a flea control powder. If brewer’s yeast is used as a dietary supplement, it may take up to a month before it reaches full flea control power. Pet owners can begin dusting their pets’ fur or supplementing their pets’ diet with brewer’s yeast in early spring, before a major flea problem occurs.
Giving a dog the tablet form of brewer’s yeast may be ineffective.
A mixture of brewer’s yeast with garlic should be avoided. Garlic is toxic to dogs and cats, with cats being more sensitive to garlic than dogs. Dogs or cats may be allergic to brewer’s yeast. If a dog or cat shows signs of an allergic skin reaction after eating flea brewer’s yeast, use of the yeast should be discontinued. Dog and cat owners should be careful about the amount of yeast they give their pets, as an overdose of brewer’s yeast can cause a skin allergy.
Considered a major pest for pets such as dogs, fleas bite and suck blood from humans and animals.
Another way to use brewer’s yeast for fleas is to allow 0.25 cups (59 ml) of yeast to dissolve in 1 liter (946 ml) of water. This solution can be placed in a spray bottle and sprayed on a pet’s fur. For maximum effectiveness, the mixture should be combed through or rubbed into the skin.