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Vectra Allergy in Cats

Vectra Allergy in Cats - Symptoms, Causes, Diagnosis, Treatment, Recovery, Management, Cost

What is Vectra Allergy?

There are many variables that can affect your cat’s skin: his food, his environment, parasites, and even things you apply on him.  Flea prevention is given to many of our pets on a monthly basis without us thinking twice about it.  It keeps them healthy and parasite free as well as keeping our homes parasite free.  What many cat owners do not realize is that their cat can actually be allergic to the flea medication they are using.  

If your cat is allergic to the vectra, he may develop skin lesions and papules, be very itchy and even experience hair loss at the site of application.  It could be one ingredient within the medicine or a combination of them that he is allergic to.  If diagnosed with an allergy to vectra, once you discontinue the use, his treatment should be straightforward and simple.  As long as his skin is treated as directed by your veterinarian, his prognosis of recovery is good.

Vectra is a type of flea prevention that can cause a contact allergy in your cat at the site of application.  If you notice hair thinning, itching, or other symptoms go see your veterinarian for an evaluation.

Symptoms of Vectra Allergy in Cats

Symptoms may include but are not limited to:

  • Pruritus¬†
  • Papules
  • Lesions
  • Crusted pustules
  • Scaling
  • Alopecia
  • Hyperpigmentation¬†
  • Excoriation
  • Lichenification¬†
  • Secondary skin infection¬†


Vectra, also known as dinotefuran, is a neonicotinoid insecticide available for the treatment and control of fleas.  The medication is absorbed by the flea on contact; it causes paralysis and death of the flea.  Vectra is a topical medication that spreads over your cat’s body once applied and adheres to the skin and fur.  It is recommended to be applied every 30 days for flea control for your cat.

Causes of Vectra Allergy in Cats

Vectra is a topical form of medication used for flea control in cats. Any type of chemical can cause a reaction in cats sensitive to it.  It can occur after just one use in very hypersensitive cats, but is seen more frequently after multiple applications of the medication.  Your cat may be sensitive to the insecticide itself or he may be allergic to an ingredient within the topical medication it comes as.  This type of allergy is considered a contact allergy.

Diagnosis of Vectra Allergy in Cats

When diagnosing a vectra allergy in your cat, the decision will be based primarily on clinical signs.  Your veterinarian will begin by performing a full physical exam on your cat.  She will make note of all his symptoms and where the condition is primarily affecting him on his body.  She will also want to collect a verbal history from you.  She will want to know details as to what your cat has ingested and has had contact with recently.  

Your veterinarian may want to perform skin diagnostics on your cat to rule out possible causes of his symptoms.  She may take a skin scraping sample from your cat to check for skin mites that can cause similar signs.  She may also take a sample for a skin cytology to check for a bacterial infection or yeast overgrowth.  These tests can rule out skin issues that may be affecting your cat.  

Once you think you have correctly selected the allergen, in this case vectra, for a true diagnosis you will need to retest it.  First, you will need to clear up the original reaction by removing the suspected allergen from your cat’s routine.  You will then need to treat the skin reaction by washing the skin thoroughly to remove any remaining liquid medication.  If there is no secondary skin infection, the lesions should clear up in 7 to 10 days once treatment begins.  Once the lesions have healed, you will now need to rechallenge the suspected allergen source; this means you will need to use the vectra again.  If it is the vectra, you can expect the lesions to reappear and/or worsen within 24 to 48 hours.  

Treatment of Vectra Allergy in Cats

Avoidance of the allergen is ideal.  There are many different medications available for flea control in cats.  There are other topical medications as well as oral medications that can work against the fleas.  If your cat is indeed allergic to vectra, an oral flea prevention may be better as he may be sensitive to other topical flea preventions as well.  

The skin will need to be treated depending on the lesions and symptoms your cat has developed.  If a secondary infection has developed from him scratching himself, your cat will need antibiotics.  Your veterinarian may also recommend a topical medication that may come in the form of a liquid, ointment, or spray for you to apply directly to the lesions themselves.  The combination of topical and oral medications will work together to heal your cat’s reaction.  

If your cat is experiencing any other symptoms, your veterinarian may need to prescribe additional  medications or therapies depending on the severity of your cat’s condition.  Each case of allergy is different but if addressed in a timely manner, treatment is straightforward.

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Recovery of Vectra Allergy in Cats

The severity of the allergy will determine your cat’s recovery process.  The more severe the allergy is, the longer it will take your cat to recover.  You must also consider the range of skin your cat has developed lesions.  If the area is small, it may be quicker to resolve and look better versus a large region.  Also, if there is a secondary skin infection present, the recovery process will take longer and need more aggressive treatment.  As long as you address the condition of the skin, his prognosis of recovery is good.

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© 2024 Wag Labs, Inc. All rights reserved.

© 2024 Wag Labs, Inc. All rights reserved.