NexGard Allergies in Dogs
Written By hannah hollinger
Published: 09/11/2016Updated: 10/21/2021
Veterinary reviewed by Michele K.
NexGard Allergies in Dogs - Signs, Causes, Diagnosis, Treatment, Recovery, Management, Cost
What are NexGard Allergies?
NexGard is a flea and tick protection system that comes in a chewable pill for dogs. This tasty and soft chew has been approved by the FDA and is considered safe for dogs. The active ingredient, afoxolaner, has been proven to effectively treat and control ticks and fleas for one month when given regularly. This item is from the makers of Frontline.
Although many dogs tolerate NexGard quite well, there are specific side effects that are listed on the label. When you are giving your dog this chewable tablet, it is essential to be familiar with the side effects that can occur. If your dog does have adverse effects to this medication, consult your veterinarian without delay.
Many flea and tick treatments do come with warnings about side effects; however, it is vital you give your dog some sort of flea and tick preventative to avoid Lyme disease and other conditions caused by flea and tick infestations. This is especially important if your dog goes outside on a regular basis and if you live in an environment where fleas and ticks are very common.
NexGard allergies in dogs occur when dogs have an allergic reaction to or suffer from side-effects of this popular flea and tick treatment. The active ingredient, afoxolaner, may not agree with all dogs that ingest this oral preventative.
Paying to treat an allergic reaction to NexGard out of pocket can be a major financial burden. Fortunately, most pet insurance companies reimburse claims within 3 days, putting 90% of the bill back in your pocket. In the market for pet insurance? Compare leading pet insurance companies to find the right plan for your pet.
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NexGard Allergies Average Cost
From 407 quotes ranging from $200 - $800
Average Cost
$400
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Symptoms of NexGard Allergies in Dogs
Signs of an adverse reaction to NexGard will vary from dog to dog. Frequently diagnosed reactions to this flea and tick treatment include:
  • Dry and flaky skin
  • Loss of appetite
  • Vomiting
  • Diarrhea
  • Lack of energy 
Types
There are various types of active ingredients in flea and tick treatments which include:
  • Pyrethrins
  • Pyrethroids
  • Etofenprox
  • Fipronil
  • Methoprene
  • Methylcarbamate
  • Imidacloprid
  • Amitraz
  • Selamectin
  • Nitenpyram
  • Fluralaner
  • Sarolaner
  • Lotilaner
Causes of NexGard Allergies in Dogs
Causes of NexGard reactions in dogs are primarily due to a reaction to the active ingredient, afoxolaner. Specific causes include:
  • The hypersensitivity towards the main ingredient
  • An over-reactive immune system
  • Afoxolaner causing skin irritation to the sensitive skin of the dog
Diagnosis of NexGard Allergies in Dogs
If you have recently started giving your dog NexGard and they are showing signs of a reaction, it is crucial to stop giving them the preventative medication and contact your veterinarian. When you take your dog to the clinic, take the package of this flea and tick preventative treatment to help the veterinarian come to a diagnosis. The veterinarian will take a closer look at the ingredients, asking questions pertaining to when the signs began.
To come to a diagnosis, the clinical team might perform various tests, such as blood work, urinalysis, and a biochemistry profile. Depending on your dog’s signs, your veterinarian may want to perform other assessments; however, this will depend on your dog's present condition.
If your dog has skin irritation, the medical professional will take a closer look to determine if a skin test is required to be sure the inflammation and soreness is a result of the NexGard. Your veterinarian may decide to wait before a costly test is conducted; once your dog stops taking the tablets, the signs may resolve. It is important to understand that this may take some time, as this flea and tick treatment is given once a month, and it may still be in their system for up to 30 days. Once your veterinarian suspects that your dog is allergic to the product, they will advise you to stop giving your companion the treatment and will recommend an alternative method to help prevent fleas and ticks.
Treatment of NexGard Allergies in Dogs
Effective treatment of a NexGard reaction will be to stop administering this chewable pill to your dog. Unfortunately, there is no immediate clinical method to remove the drug from your pet's system but depending on your dog's condition, supportive treatment may be offered. Treatment methods that can help in the meantime are:
Topical Medications
Applying a topical medication to your dog’s skin, if the reaction caused a skin irritation, will ease the sensitivity and discomfort. Topical medications may help your dog stop itching and licking the skin.
Alternate Preventatives
Finding an alternate preventative for your dog’s flea and tick treatment is essential. You may want to research other alternatives to keep your dog free of these parasites. Do not try to treat the fleas and ticks without consulting your vet in case your dog has a sensitivity to other products. Your medical professional can also suggest specific flea and tick treatments.
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Recovery of NexGard Allergies in Dogs
If your dog is often outdoors it will be important to find protection against infestations that works for them, yet does not include such harsh ingredients. Protecting your pet from fleas and ticks prevents more serious conditions from occurring, such as Lyme disease and other illnesses.
Once you find an alternative that works for your dog, it may take them some time to adjust. Monitor your dog’s skin and coat for infestations to be sure the new preventative is working properly.
If your dog develops signs of a reaction after you have removed the Nexgard chewable from their diet, contact your veterinarian. Your veterinarian may then decide to do further allergy testing to identify the ingredient they are allergic to.
NexGard Allergies Average Cost
From 407 quotes ranging from $200 - $800
Average Cost
$400
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NexGard Allergies Questions and Advice from Veterinary Professionals
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Kelpie cross beagle
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8 weeks
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0 found this helpful

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0 found this helpful

My pet has the following symptoms:
Itchy
I have given my two eight week old puppies Nextgard Spectra lunchtime Friday and they are both still quite itchy and forever scratching. Does it take a few days to fully take effect or is it likely to be something else?
Sept. 28, 2020
Answered by Dr. Michele K. DVM
0 Recommendations
Thank you for your question. It may be something else. There are other parasites that can affect puppies, and if they are still very itchy, it would be a good idea to have them seen by a veterinarian, as they can look at their skin and see what might be causing the problem. I hope that they feel better soon!
Oct. 7, 2020
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Blue Heeler
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dog-age-icon
7 weeks
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0 found this helpful

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0 found this helpful

My pet has the following symptoms:
Lethargic, Diarrhea, Vomiting
I took my blue heeler puppy this past Thursday for his six week puppy shots where he received nexgard and interceptor plus per the vets recommendations. He has acted fine until tonight, which he has started throwing up every bit of food in his stomach, doesn’t want to drink water nor milk and has no energy to even get up and move, I don’t know what to do at this point he’s only had two bouts of diarrhea so far but neither has smelled like Parvo virus nor had blood in it. I hope you can help
Aug. 5, 2020
Answered by Dr. Michele K. DVM
0 Recommendations
Thank you for your question. While those medications can cause mild GI upset, they don't typically cause signs as severe as you are describing. I would be very concerned about Parvo virus, and it would be best to have your veterinarian run a Parvo test on him. Parvo virus does not always start out with blood in the stool, and can often start with lethargy and a loss of appetite. I hope that he is okay.
Aug. 5, 2020
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German Shepherd
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Fourteen Weeks
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14 found this helpful

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14 found this helpful

My pet has the following symptoms:
Diarrhea
Is it common for my puppy to get diarrhea the day after nexgard treatment start
Aug. 3, 2020
Answered by Dr. Michele K. DVM
14 Recommendations
Thank you for your question. Nexgard does sometimes cause a little GI upset or diarrhea, especially if it is not given with food. Giving it with a full meal can help prevent that next month. If he continues to have diarrhea, or starts vomiting or is lethargic, then it would be best to have your puppy seen by a veterinarian as soon as possible. I hope that all goes well for your pup!
Aug. 3, 2020
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Labrador Retriever
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Twelve Weeks
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11 found this helpful

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11 found this helpful

My pet has the following symptoms:
Swollen Eye
He had vaccination yesterday with his vet. Today morning at 7am I gave him nexgard and He developed swelling on his left eye at 10:30am . Should we take him to the emergency.
Aug. 1, 2020
Answered by Dr. Sara O. DVM
11 Recommendations
Hello, So sorry to hear about your dog. It does sound like he is having a reaction to something. If the swelling continues, you may need steroids from your vet. You can try Benadryl at 1mg per pound to see if that helps but if not it would be best for a vet to look at him.
Aug. 1, 2020
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Mini poodle
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One Year
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3 found this helpful

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3 found this helpful

My pet has the following symptoms:
Nasty
He gets nasty after giving him NEXGARD I don’t know if it’s a side effect of dizziness or nausea it happens each month for the past 7 months
July 31, 2020
Answered by Dr. Michele K. DVM
3 Recommendations
Thank you for your questions. I'm not sure what nasty actually means, but if your dog has an abnormal reaction to that medication, it might be best to switch to another medication. There are many flea and tick prevention available, and your veterinarian would be able to advise on other Alternatives. I hope that all goes well for your dog.
Aug. 1, 2020
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Staffordshire Terrier
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Brooklyn
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5 Years
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0 found this helpful

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My pet has the following symptoms:
Vomiting Diareha
Vomiting , Diarrhea Very Ti
Vomiting , Diarrhea Lethargic
Can a dog have reactions even though they taken it in the past . I gave her a dose yesterday and vomited . Woke up this morning she vomited in the bed and carpet . She’s just laying on the floor . I’m worried about her .
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pitbull
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Zino and Sasha
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18 Months
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0 found this helpful

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My pet has the following symptoms:
Weight Loss
Jaw Chomping
Hair Loss
Drooling
Skin Lump
Jaw Clenched
you fuckers... I have had my two APBT's go through months of allergic reactions.. and thousands of rands in new foods, vet bills,sleepless nights for months to get to an understanding of why they have been losing hair and skin bumps (impedigo), as well as lack of energy and weight loss as well as drooling and clentched jaws when sleeping and the only constant I have not changed is the administering of nexgaurd.. its day 18 of the month and cant wait to get them clear of that so called medication.. I am going to take this further and make as many people aware of the terrible substance that you are marketing to people that trust ..your company is going to be shut down for this --frontline.. you will and must be paying already for this in the heavens..God will ensure everyone get their dues.. that I promise.
NexGard Allergies Average Cost
From 407 quotes ranging from $200 - $800
Average Cost
$400
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