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Kills Fleas |
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Repels Fleas |
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Kills Flea eggs and Larvae |
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Kills Ticks |
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Repels Ticks |
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Kills and/or Repels Mosquitoes |
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Prevents Heartworm |
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Other Parasites Information | NA | Eliminates infestations with chewing lice, aids in the control of sarcoptic mange infestation | |
Waterproof (shampooing once a week can reduce effectiveness) |
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NA |
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Safe for pregnant or nursing Pets |
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Consult with your veterinarian before using this product on debilitated, aged, pregnant or nursing animals. |
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How long does it take to work | Reapply Activyl every 30 days. | Starts killing fleas in 30 minutes, and kills 98-100% of fleas in 12 hours. | Kills Fleas within 12 hours and Ticks within 48 hours |
Taste | Applied to skin | Topical application | Applied to Skin |
Active Ingredient(s) | indoxacarb | Spinetoram | Fipronil/(S)-Methoprene |
RX Required |
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Dosage | Monthly | ||
Usage |
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Video | Coming soon | Coming soon | Coming soon |
Vet Review | Another recently available new topical flea preventative for dogs and cats. This new product works by being activated by only the flea's enzyme systems into a flea specific mechanism which paralyzes and kills the adult flea. The company claims that it does not get into the blood stream, but stays only in the superficial skin layers of the pet. Any adult fleas which come into contact with this product are quickly killed so that fleas do not have to actually bite the pet, which is tremendously helpful in those flea-allergic pets, where it only takes a few flea bites to set off an extensive itchy allergic reaction. Another wonderful benefit of this product is that it is waterproof, which is especially helpful in those active outside pets who are exposed to rain or like to swim. This effective product starts working within 12 hours of application, where over 90% of adult fleas are killed. Another excellent benefit of this product is that it also inhibits the development of flea eggs and larvae in the environment, which is a big bonus since much of the flea life cycle occurs in the home environment. While Activyl is very safe and effective for most pets, I have seen occasional rare reactions in sensitive pets, which most commonly is seen as irritation or excessive itchiness at the site of application. While the company says that it is odorless, some of my clients have said that they do sense an odor within the first several days of application, as well as leaving an occasional oily film for the first day or two following application. This film, however usually quickly disappears. The only other very rare reactions include digestive upset and/or drooling/neurological reactions, and certainly if a pet has any chronic digestive weaknesses or history of seizures, etc then the local veterinarian should be consulted before applying the product. I give this product an overall rating of 4, with an ease of use of 4. | Fleas are easily the most common external parasite that plague cats throughout the country. Fleas have been shown to not only cause weakness and anemia in affected cats, but also transmit dangerous infectious diseases, including bartonellosis, an also increasing threat to humans. Cheristin is made with the same main ingredient as Comfortis for cats, and acts uniquely on the nervous system of the flea. Unlike flea prevention tablets, Cheristin starts killing fleas within 30 minutes and almost 100 percent of fleas within 12 hours. With the easy to use applicator, this product has been shown to be quite effective for one month. The most common, yet rare side effect I have seen in cats is an allergic reaction or hair loss at the site of application, and even less commonly vomiting and lethargy. It is an excellent and fast acting, effective product with an overall rating of a 4.5 with an ease of administration of a 5. | I find that the effective combination of an ingredient like fipronil, along with the insect growth regulator methoprene, provides the best spectrum of activity and protection against all stages of the flea life cycle from egg through larval stage on to adult. Because of these two main ingredients and their method of action, I find that clients don't have to treat the environment as much. I find that this product tends to be safer in smaller breed animals when compared to its competition. I find its tick efficacy quite good. The fact that it is waterproof also allows clients, whose pets swim frequently, to confidently use this product during the swimming months. I also find that this product works the longest for fleas, while some of the competitive products have to be reapplied before the end of the month. The lack of label efficacy against mosquitoes and flies, as well as the fact that this product does not repel fleas or ticks are the two main disadvantages. As with any insecticidal products, I find that every pet is an individual, in terms of which of the products works best on them. When I am dealing with more of a flea issue in a patient, this is the product I will likely reach for first. |