DEAR READERS: This post was written over a year ago. I’ve never sold Certifect in my hospital, and have no experience with it in clinical practice. Please contact your veterinarian, or Merial, if you have questions. Thanks!
DEAR READERS, PART 2: Certifect does NOT contain enough amitraz to treat Demodex, says Merial. Ask your vet for other options.
CERTIFECT™ is like FRONTLINE® Plus but with amitraz added?
By now, hopefully all pet owners know that ProMeris® for Dogs is no longer being manufactured by Pfizer, after a study suggested ProMeris® might cause Pemphigus foliaceus, an immune system mediated skin disease, in some dogs.
ProMeris® contained a combination of metaflumizone and amitraz. It is unclear if the amitraz portion of ProMeris® had anything to do with the Pemphigus. We do know that amitraz on its own, which has been used for years and years in products like Mitaban®, causes no such diseases.

CERTIFECT™ is NOT made by the people who made ProMeris®.
In my personal and clinic experience, ProMeris® smelled HORRIBLE, ate paint off of surfaces if a dog wearing it happened to lean against something, and caused local skin reactions including scabbing and hair loss in about 2% of all dogs receiving it. Was it the metaflumizone? Or the carrier that the metaflumizone and amitraz were in? Did they make it with used motor oil or something?!
Anyways, none of this was Pfizer’s fault, since they gained control of ProMeris® when they acquired Wyeth / Fort Dodge Animal Health in 2009. Pfizer also makes revolution®, a prescription topical that prevents fleas and heartworms, and is a fabulous drug. Obviously Pfizer thinks they can sell more revolution® than ProMeris®. Hooray Pfizer! Good riddance to ProMeris!
So now, a competing company – Merial, makers of FRONTLINE® Plus – is coming out with a drug they call CERTIFECT™, advertised as “a better way to detach and kill ticks”. CERTIFECT™ is essentially modified Frontline Plus with our old friend amitraz added.
So, if ProMeris® sales fell flat, I wonder what makes Merial think CERTIFECT™ will fare any better? Merial claims the tiny amount of amitraz added to CERTIFECT™ improves its tick-repelling profile. Therefore, CERTIFECT™ works better against ticks than their other tick-labelled product, FRONTLINE® Plus.
Amitraz and therefore CERTIFECT™ must be used carefully, and only in selected patients
Veterinarians have been concerned about the safety profile of amitraz for years. It’s a powerful drug, and does lots of great things if you use it carefully.
The pharmacological action of amitraz is not well understood, but it is a monoamine oxidase inhibitor (MAOI) in mites and may have effects on the central nervous system of susceptible organisms. Amitraz can cause a significant increase in blood sugar levels in patients, and should not be used on “fragile” diabetics. In cats, we know that amitraz ingestion (ie: from self-grooming) can cause sedation similar to that caused by alpha-2 agonists such as dexmedetomidine (a common veterinary injectable sedative).
Other, much more concentrated amitraz containing products have included instructions like:
1. Flammable until diluted with water
2. Do not stress animals for at least 24 hours after application.
3. Protect exposed skin with rubber gloves, etc.
4. Wash hands and arms well after application to animal.
5. Avoid inhalation of vapors.
6. Animals treated may exhibit signs of sedation; if animal is un-arousable or sedation persists for longer than 72 hours, contact your veterinarian.
7. Safety of amitraz has not been demonstrated in dogs less than 4 months of age.
8. Reproductive safety has not been established.
9. Toy breeds may be more susceptible to CNS effects (transient sedation).
10. If treating around eyes, use an ophthalmic protectant (e.g., petrolatum ophthalmic ointment) before treating.
11. Other adverse effects include: dizziness, slow heart rate, vomiting, diarrhea, hypothermia and high blood sugar levels.
12. Can be toxic to cats.
13. May interact poorly with selegiline (L-deprenyl, AniprylⓇ, used for cognitive dysfunction in dogs), or tricyclic antidepressants (amitriptyline, climipramine / ClomicalmⓇ).
Merial should address safety of amitraz-containing CERTIFECT™
As you might be able to tell, I was not a fan of ProMeris. I never did sell it.
So here’s my problem. Nobody denies that amitraz is an outstanding anti-tick drug. I get it, that’s cool, it’s good stuff when used gently and with veterinary supervision, on certain young healthy dogs.
But shouldn’t Merial learn from the errors of predecessors and BEGIN their marketing campaign by reminding veterinarians about the bad things that amitraz can do? And instead of a campaign called “A New Standard in the Fight Against Ticks That May Carry Disease” perhaps go with something more like “If FRONTLINE® Plus isn’t repelling and killing ticks fast enough for your liking, please ask your veterinarian if it would be safe for you to try CERTIFECT™“.
Or how about just “it’s not as bad as ProMeris®, we promise!”
Pet owners, understand that CERTIFECT™ doesn’t contain any “new” molecules, only old ones in new combinations. Many of the old warnings may therefore still apply.
None of this is intended as directed against Merial, which as a company has created some VERY helpful veterinary drugs for many years. (IVOMEC® / HEARTGARD®, HEARTGARD® Plus , FRONTLINE® , FRONTLINE® Plus , and some truly outstanding vaccines).
I just wish that the general public could be warned about known, potential hazards BEFORE CERTIFECT™ gets much further into its launch. By the time most people Google Certifect and find this post, the product will probably be all over the marketplace.
If you accidentally put CERTIFECT™ on your cat, even though the label specifically told you not to, please contact your veterinarian right now.
As for Leo’s Pet Care and our clients, I will recommend a common-sense approach: wait for others to try it first. Once CERTIFECT™ has been on the market for a year or two, and a more complete safety profile has been determined, then you can consider putting this on your young, healthy dogs, if ticks are a big problem where you live.
If that’s not your dog, maybe just stick with good ol’ Frontline. Or, better yet, instead of old-school FRONTLINE® Plus or amitraz-containing CERTIFECT™, buy some Vectra 3D® from your veterinarian.






