Internal Powder is a special blend of dark brewer’s yeast, garlic, B vitamins, minerals and special nutrients that work together synergistically and more effectively for fleas than yeast and garlic alone. Taken orally, the Powder produces an odor that is undetectable by humans and is loathed by fleas and ticks, mosquitoes, and black flies. Taken regularly, the Internal Powder makes your animal less attractive to infestation. All ingredients are human food grade with no insecticides, chemical preservatives, salt or sugar. IT WORKS! Over 20 years of testimonials prove this product really works.