Osurnia Otic Suspension (Florfenicol, Terbinafine, Betamethasone) for Dogs

Overview of Osurnia Medication for Dogs

  • Osurnia is a medication to treat ear infections in dogs. Otitis externa (outer ear infections) commonly include infection with both bacteria and yeast organisms. Many medications designed to treat these infections will include multiple medications to treat all aspects of the infection. You can learn more about otitis externa in these articles from the Petplace library: Otitis Externa (Ear Infections) in Dogs and Otitis Externa (Ear Infections) in Cats. 
  • Osurnia contains 3 medications to treat your pet’s otitis externa:

    • Florfenicol – a bacteriostatic antibiotic that will treat a wide variety of bacteria types found in ear infections.
    • Terbinafine – an antifungal medication used to treat infections caused by fungi (yeasts and molds). It is effective in the treatment of the common skin and ear yeast Malassezia pachydematitis.
    • Betamethasone – a glucocorticosteroid that will help reduce inflammation and itching in the ear canal. Inflammation is a large source of the pain associated with otitis, this will help your pet become comfortable more quickly.
  • Osurnia is specifically used to treat of otitis externa caused by susceptible strains of yeast (Malassezia pachydermatis) and bacteria (Staphylococcus pseudointermedius).

Brand Names

  • Osurnia® – Elanco Animal Health
    Similar multi-drug products include:

    • Tresaderm (Merial) which includes Neomycin sulfate, dexamethasone and thiabendazole
    • Otomax Ointment (Intervet-Schering-Plough) which includes Gentamicin sulfate, betamethasone valerate and clotrimazole
    • Posatex (Intervet/Schering-Plough Animal Health) which includes Orbifloxacin, posaconazole, mometasone furoate monohydrate
    • Generic formulations which contain Neomycin, polymyxin B, and hydrocortisone (generics)
    • Surolan (Vetoquinol) which includes Miconazole nitrate, polymyxin B sulfate, prednisolone acetate
    • Mometamax (Elanco Animal Health) which includes clotrimazole, gentamicin and mometasone

Uses of Osurnia in Dogs

  • Osurnia is prescribed to treat or control infections caused by susceptible yeast and bacterial ear infections (otitis externa). The product is currently labeled for use in dogs only.
  • Osurnia is not effective against infections caused by viruses or parasites (such as worms or mites).
  • Identification of the cause of an ear infection should be undertaken by your veterinarian.

Precautions and Adverse (Side-) Effects of Osurnia

  • The combination of florfenicol, terbinafine, betamethasone found in Osurnia® is generally safe for use in dogs.
  • Your pet should be examined by your veterinarian before starting this medication, it should not be used in animals with a ruptured ear drum (tympanic membrane).
  • Signs of allergy to Osurnia® may include skin reactions, hives and redness of the treated area.
  • Use of Osurnia® can potentially be associated with partial hearing loss in a small number of dogs. It can be temporary in some dogs.
  • If you notice hearing loss, head tilt or dizziness in your pet undergoing treatment with Osurnia® stop the treatment and call your veterinarian immediately.
  • The steroid component of Osurnia®, betamethasone can cause suppression if the adrenal gland and interfere with testing for disorders of the adrenal gland.
  • This medication has not been evaluated for use in breeding, pregnant or lactating dogs.

How Osurnia® is Supplied

Osurnia® is available in single use tubes with a flexible soft tip.
The ear canal should be cleaned and dried before the topical use of this product.


Dosing Information for Osurnia for Dogs

  • This drug should only be used under direction of a veterinarian. It may not be safe to administer the combination of florfenicol, terbinafine, betamethasone to pets with certain medical problems.
  • The typical dose of Osurnia® is the same for all dogs, the entire tube is squeezed into the ear canal. This dose is repeated in 7 days. The ear canal should not be cleaned for 45 days for all the gel to contact the canal.
  • The duration of administration depends on the severity of the infection, response to the medication, and the presence of any adverse effects. Be certain to complete the prescription.



Vectra 3D Toxicity in Cats

Fleas are frustrating and annoying insects that thrive on our dogs and cats and many flea products safe for use on dogs can be toxic to cats, such as Vectra 3D. The component in Vectra 3D that is toxic to cats is “Permethrin”.

Getting rid of fleas is an important and sometimes difficult process. Fortunately, many products are available to reduce the flea population within our homes and on our pets. The most popular products include those supplied in small tubes that are applied to the back of the animal. This type of product generally lasts for about 30 days. The focus of this article is to discuss the toxicity of Vectra 3D, a product marketed for dogs, when cats are exposed either by application or contact with a dog with a recent application.

What is Vectra 3D?

Vectra 3D is a topical insecticide medication applied to the skin of dogs to repel and kill fleas, ticks, mosquitoes, biting and sand flies, lice and some mites. This protection lasts one month after application.

Vectra makes a topical product for cats and kittens that contains the drugs dinotefuran and pyriproxyfen. The Vectra 3D product contains these same medications plus permethrin which makes it only for dogs, as permethrin is an insecticide that is highly toxic to cats.

For more information on flea product toxicities and the toxic component of Vectra 3D, see also Permethrin and Pyrethrin Toxicity in Cats.

Overview of Feline Permethrin Toxicity

Permethrins, a class of synthetic insecticide, has a much greater potential for resulting in toxicity than it's natural counterpart, pyrethrins. Permethrin based topical flea products are usually labeled "for use in dogs only." There is a wide safety margin for permethrins in dogs. Cats, however, are exquisitely susceptible to the toxic effects of permethrins. Application of permethrin-based insecticide, like Vectra 3D to a cat will usually result in toxic signs within 6 hours.

What to Watch For

  • Drooling
  • Paw flicking or ear twitching
  • Lethargy
  • Muscle tremors
  • Vomiting
  • Difficulty walking/ataxia (stumbling when walking)
  • Seizures

Diagnosis of Vectra 3D Toxicity in Cats

The diagnosis of Vectra 3D (permethrin) toxicity is based on physical exam findings as well as a recent history of topical flea product application. There have also been reports of cats developing a toxicity when they are directly exposed to the product after it has been applied to a dog in the house or they groom the product off of a canine housemate. Although skin and hair tests can be done to confirm the presence of insecticide, those results may take several days and are often received too late to aid in treatment.

Treatment of Vectra 3D Toxicity in Cats

Treatment involves eliminating any existing product from the body and controlling seizures and muscle tremors. Expect your veterinarian to recommend hospitalization with continuous intravenous fluids. Additional recommendations for treatment may include:

Bathing with a mild dish soap (such as Dawn®) with lukewarm water to remove additional flea product from the pet's skin and reduce the amount absorbed.

Administering diazepam or phenobarbital for seizure control.

Administering methocarbamol to treat muscle tremors. This may be given multiple times throughout the hospital stay. This medication is usually started as an IV injection and can be continued with the oral pill when your cat's signs are improving.

For cases with severe signs or those that do not respond to the above therapy, another treatment option is intravenous lipid emulsions (IVLE). This is a solution of medium or long chain triglycerides and is primarily used in critical patients as part of an intravenous nutrition protocol. It has been found that these lipid solutions can help in toxicities that are fat soluble like Vectra 3D (permethrin). Side effects are rare with one time use of the lipid emulsions but can include irritation of the vein where administered (phlebitis), jaundice, anemia, inability of the blood to clot, and a low platelet count. The most common side effect is hyperlipidemia (elevated fats in the bloodstream). This treatment has shown great promise in reducing the signs of toxicity and decreasing the amount of time these cats need to be hospitalized.

If treated early, the majority of pets suffering from Vectra 3D toxicity recover enough to go home within 24-48 hours, although fine muscle tremors may continue for several days. Severity and the length of time that toxicity lasts will depend on the amount of Vectra 3D your cat was exposed to and how sensitive your pet is to this toxicity.