Adverse Reactions to Advantage Flea Control

Advantage is a topical product that is used to treat and control flea infestations on household pets. According to the Bayer Animal Health Division, Advantage works by halting flea bites within five minutes of application. It also kills off between 98 and 100 percent of fleas on the affected pet within 12 hours of the initial application. As with any medication, Advantage flea control can have various unwanted side effects. It is important for any pet owner to be aware of the potential side effects of a new medication being used on their pet.

  1. Pruritus

    • In a field study done by Bayer Pet Health, 19 out of 61 flea-infested dogs suffer from pruritus. Pruritus is a condition in which chemical reactions in the skin and nerves cause the dog to itch. The itching can be mild or severe and can also include biting or licking of the skin. If left untreated, the dog may begin to lose hair and suffer from painful skin lesions.

    Lethargy

    • In a laboratory effectiveness study performed by Bayer Animal Health, one dog and three cats experienced lethargy. The affected animal may appear to be drowsy or inactive. The owner may also note that the pet has delayed responses to stimuli such as being petted or various sounds or visual stimulation. In an extreme case, one cat slept for two days without movement in the exact same place.

    Changes in Behavior

    • When Advantage Multi for Cats was applied to a group of 215 cats, 9 cats experienced noticeable changes in behavior as noted by their owners. Different changes will vary from household to household but can include excessive grooming or changes in overall grooming habits, hiding, agitation, spinning in circles and pacing.

    In Kittens

    • In a study performed on 48 nine-week old kittens, Advantage Multi for Cats was applied at several different dosages. Dosage amounts included the recommended dosage, three times the recommended dosage and five times the recommended dosage. Many side effects occurred in the kittens who were treated with three and five times the recommended dosages and included lethargy, disorientation, scratching at the site of application, slowed responses to light and hyper salivation.

    In Puppies

    • In another safety study performed on 7-week old puppies, Advantage Multi for Dogs was applied at the recommended dose and at three and five times the recommended dosages. In this study, the topical medication was applied every 2 weeks for 12 weeks. Puppies had fewer reactions than the kittens and some adverse reactions included vomiting, lack of appetite, difficulty breathing and pruritus.