The direct answer to this question is yes. However, I will state plainly and unequivocally it is not brewer’s yeast or garlic. Naturally minded pet owners need to stop living in denial about brewer’s yeast and garlic as legitimate flea preventive agents: FACE FACTS, THEY DO NOT WORK. The actual answer will be quite surprising to most naturally and holistically minded pet owners. But first, a little background is in order.
Scientists have for some time observed that plants that grow in soil laden with species bacteria called Saccharopolyspora spinosa were conspicuously devoid of insect pests. Further research determined that the reason behind the insecticidal properties of the soil was due to a secretory molecule within the bacteria called spinosad. Specifically, while posing little toxicity risk to mammalian species, spinosad is highly toxic to an adult insect’s nervous system, with contact leading to rapid and high mortality rates in many species of insects, most notably, fleas.
Pharmaceutical Eli Lilly has been able to isolate and mass produce spinosad in two of their animal health division’s marquis products for dogs and cats: monthly oral flea preventive Comfortis, and monthly oral heartworm and flea preventive, Trifexis. A spinosad derivative called spinatorem is available for cats, administered as a monthly topical flea preventive. In either form, isolated and mass produced by a pharmaceutical, spinosad is still by in large considered to be a natural isolate and insecticide, to the extent that a garden may still be legally identified as “organic” if spinosad is applied for insect control.
This is where so many naturally minded pet owners are quite surprised at my answer when they ask me if there are any natural or holistic flea prevention/control options available. They expect me to tell them that brewer’s yeast, garlic, cedar sprays, ultrasonic emitters, and other natural modalities that are popular internet pet forum talking points but do not actually work for prevention of fleas, are the answer; when the only currently proven natural flea prevention solution comes from a multibillion dollar a year pharmaceutical company.
Dr. Roger Welton is a practicing veterinarian and highly regarded media personality through a number of topics and platforms. In addition to being passionate about integrative veterinary medicine for which he is a nationally renowned expert, Dr. Welton was also an accomplished college lacrosse player and remains to this day very involved in the sport. He is president of Maybeck Animal Hospital , runs the successful veterinary/animal health blogs Web-DVM and Dr. Roger’s Holistic Veterinary Care, and fulfills his passion for lacrosse through his lacrosse and sport blog, The Creator’s Game.