How Safe are the Newest Flea Preventatives?
What do you think of Comfortis? I just started
giving it to my Labs and wondered about the safety
of it. It is doing a good job on the fleas.
Scott
Tulsa, OK
Two popular new flea preventatives have come onto the market recently. One, Comfortis, is an oral pill taken once monthly available only for dogs. Unlike topical spot-on flea preventatives, Comfortis does not force dogs to endure a greasy patch of skin each month. Also, a small number of dogs have local skin reactions after topical treatments are applied. Comfortis avoids this problem as well.
The safety profile of Comfortis appears to be good. However, I don’t have much personal experience with the medicine. Most of my patients do fine with Frontline, Advantage, or Revolution so I have not had much interest in rocking the boat. However, I am happy to have another option for future use.
The other popular new flea preventative is ProMeris. Promeris is a topical product that kills fleas and ticks and is available for both dogs and cats. It was released with great fanfare to the veterinary community. However, like Comfortis, it has yet to become as widely used as the more established flea and tick medicines.
Shortly after the release of ProMeris, I received an urgent e-mail from a client. It had been forwarded around the world by dozens of people, but my client assured me that the source was a friend of a friend who was absolutely reliable. The e-mail claimed that ProMeris is very dangerous and may cause horrible side effects in dogs and people.
Having learned a while back that sometimes one encounters false information on the internet, I did what any scientifically-inclined individual would do under such circumstances. I looked up ProMeris on snopes.com.
The result was that the claims of severe reactions can be neither proved nor disproved. From the snopes page:
Just about any product used with animals, no matter how generally safe, can produce adverse reactions in some cases due to misuse . . . or unusual sensitivity to one or more ingredients in individual animals.
I couldn’t have said it better myself. The general safety profile of ProMeris appears to be good, and I have yet to personally encounter any animals who have had severe adverse reactions to it.
Although I do not yet have extensive experience with Comfortis or ProMeris, I most certainly have a great deal of experience with fleas. Fleas are vile, bloodsucking, disease-spreading, misery-causing pests. Have I mentioned that fleas once killed a third of the people living in Europe? Fleas spread the Bubonic plague.
So, my assessment of the newest flea preventatives is this: they almost certainly are safer and generally more healthy for pets than fleas.
You have questions. 
I’m a vet tech at a local Tulsa hospital and we have had incredible success with Comfortis. We discontinued use of ProMeris after several patients experienced EXTREME reactions to it. The application site looked like burn wounds. It was extremely traumatic to both pet and owner. The reaction on my own skin was actually very similar, but my skin is very sensitive and I also react to Frontline, only not as severely.
Dr. Barchas,
I just adopted a 3 months lab/pit mix puppy and gave him comfortis five days ago. I had used comfortis before with my older 9 year old daschund and had no problems. I asked my new vet about comfortis for the puppy and she was happy to provide me with a six months supply. My puppy is experiencing all the side effects of vomitting, lack of appetite, lathargic and I am greatly concerned. I have been on the phone with the vet every day and she has not been able to pin point these symtoms to confortis. What can I do? How long will comfortis stays in the system? The puppy is refusing to eat and has not been able to keep anthing down even after it was forced fed.
Pets giving happiness to us…Pets health is important to all..Flea control is used to prevent the pets from flea.
Thanks to gave good information for caring health of pets..You gave two more flea control products usage. It will be helpful for all pets owners..
Topical products like Frontline and Advantage seem to work very well. I have used these products for many years on my pets and have never had any problems. Comfortis works well for fleas only. The problem with Comfortis is there is no tick control. Ticks are a major problem along with fleas. They carry Lyme disease which we can also get.
I have two little dogs (Shih Tzu mixes) and live in Florida. They need flea and heartworm preventive all year long due to the warm climate. I used Comfortis when it came on the market and one of my dogs began having seizures. The other dog tolerated it with no side effects. I have returned to using Frontline & Heartguard with no problems. I really like the convenience of Comfortis, however, our dogs are just like we are. Some can tolerate a medication with no side effects, others can not.