How Long Can a Dog Go Without Flea Medicine?

Dogs can easily become infested with fleas without regular prevention.
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Your dog should be given flea prevention on a regular schedule, determined by the product you use and your veterinarian. Most prevention solutions should be given monthly, from topical to oral products. Delaying administration of the medicine can allow your dog to be exposed to fleas, often leading to disease risks and allergies.

Preventing Fleas

Your dog may never receive flea prevention and be fine, but most dogs need it monthly to prevent infestations. The American Veterinary Medical Association provides guidelines for owners on safe flea prevention, recommending you always read product instructions for effective use and discuss possible flea solutions with your veterinarian. By waiting a longer duration before giving your dog his next dose, you allow him to bring fleas home with him. Once an infestation occurs, it can take months to stop the flea life cycle in your home. These fleas can make your pet very itchy, lead to anemia or give him tapeworms.