The Trifexis Debate

Working as Neurology technicians, we are regularly asked questions from owners pertaining to the daily care and maintenance of their beloved pets. These questions range from diet standards to bowel movement regularity. One question I have commonly been asked since working at Live Oak Veterinary Neurology is regarding the safety of using Trifexis. I believe that the majority of canine owners are aware of, or heard about, the WSB-TV Atlanta story by Jim Strickland linking several canine deaths to the use of Trifexis. My intent of this blog is to discuss our practice’s views on the use of Trifexis.

In order to write a well-informed blog on this topic, I reached out to several representatives of Elanco, producers of Trifexis. Through multiple conversations, assessment of FDA research, and discussing the topic with Dr. King, it is our practice’s opinion that Trifexis is a safe and effective tool in the fight against those pesky fleas and deadly heartworms.

Visit the  American Heartworm Society website  to learn more about these deadly parasites.

Visit the American Heartworm Society website to learn more about these deadly parasites.

With that said, when a client consults with our neurologist about their pet’s epilepsy, we recommend they not use Trifexis or Comfortis. The reason being, when we manage seizures, we want to be able minimize any external variables that could affect the pet’s symptoms. The component of Trifexis that controls fleas, spinosad, also the main drug in Comfortis, crosses the Blood Brain Barrier (BBB). The BBB’s sole purpose is to control what chemicals can get into the brain. With spinosad’s ability to cross the BBB, its presence is one factor in the patient’s epileptic mystery that we can control. Seizures are a brain disease so controlling what comes and goes is our main objective.

According to the research conducted to get the medication approved by the FDA, giving Trifexis or Comfortis does have its risks, just like any other medication out there. The most commonly seen side effect is vomiting. Many times this can be alleviated by just adjusting the way that you give the medication. I strongly recommend that, if you are seeing these side effects, contact your veterinary team or Elanco directly on their Technical Support line.

For questions regarding the use of Trifexis or Comfortis, please contact Elanco at 1(888)545-5973 or visit their website at

If you feel that your pet is experiencing a side effect of Trifexis or Comfortis, please contact Technical Support at 1(888)545-5973 and speak with the company’s technicians or veterinarians.