Credelio vs. Nexgard: Which Flea Medication is Better?

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There are many joys of having dogs part of your life.

However, fleas are not one of them.

Fleas are far more than a nuisance; they can be hazardous to your dog’s health, causing issues such as anemia, dermatitis, and tapeworms[1].

The best way to battle fleas is to avoid them altogether. Using preventative medications such as Credelio and NexGard can make all the difference.

But with numerous flea preventatives to choose from, it can be challenging to know which is best.

This article, Credelio vs Nexgard, compares these two chewable flea and tick preventatives.

Below, I will introduce how they work, pros and cons, side effects, and more.

Spoiler Alert: My preference between the two options is NexGard because it is a bit safer when it comes to possible side effects, it is effective against mites, and it is FDA-approved to prevent infections that cause Lyme Disease.


  • Active Ingredient: Lotilaner
  • Type: Oral Chewable Tablet
  • Duration: 1 Month

Credelio is an Elanco product.

Elanco has been helping pet parents keep their pets safe for over 65 years and is an American based company.

In addition to Credelio, Elanco manufactures vaccines, medications, and pet therapeutics.

Credelio uses the lotilaner pesticide to kill fleas and ticks. It starts eliminating fleas and ticks in just 4 hours and is 100% effective at 24 hours[2].

Lotilaner is a parasiticide that fatally interferes with the nerve receptors.

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Credelio kills Lone Star ticks, American dog ticks, Brown dog ticks, and Black-legged ticks.

You can find more in-depth info in our review of Credelio flea treatment.


  • Goes to work in just four hours
  • Easy to administer
  • Extra purified for easier digestion
  • Kills four varieties of ticks


  • The parasite must ingest the lotilaner from biting the dog for the medicine to work
  • Contains pork, wheat, barley, lactose, and soy

If Credelio is right for you, click here and get your order started!


  • Active Ingredient: Afoxolaner
  • Type: Chewable Tablet
  • Duration: 1 Month

NexGard is manufactured by the Boehringer Ingelheim Group.

Boehringer Ingelheim Group’s goal is “to improve the quality of life of humans and animals.” Boehringer Ingelheim is a family-owned global company.

NexGard is a beef-flavored chewable that uses afoxolaner, a parasiticide that disturbs the flea and tick’s nervous system.

NexGard starts killing fleas in 4 hours and ticks in 12 hours[3].

NexGard kills Black-legged ticks, American dog ticks, Lone Star ticks, and Brown dog ticks.

In addition to fleas and ticks, NexGard is effective against three different varieties of mites: Sarcoptes, Demodex, and Otodectes.

Related: Nexgard vs Nexgard Spectra: Which One is Right for Your Dog?


  • Ideal for dogs with food allergies or sensitivities to gluten and animal proteins, though it does contain soy
  • Works in just four hours
  • Protects against mites
  • Only FDA-approved tick protection to prevent Lyme Disease infection[4]


  • The parasite must ingest the afoxolaner from biting the dog for the medicine to work
  • Does not work as a parasite repellent

Ready to order NexGard? Click here to get started!

If you want to learn more about NexGard, check out our NexGard review!

Credelio vs NexGard Compared

Below I have pulled together information for a side by side comparison for Credelio and NexGard.

I think the chart makes it faster and easier to compare the two products.

Kills Fleas and TicksYesYes
Repels Fleas and TicksNoNo
Other ParasitesDemodex mites, Sarcoptes Mites, and Otodectes mites Nothing listed
Active IngredientAfoxolanerLotilaner
Duration1 Month1 Month
Prescription NeededYesYes
Waterproof or Water ResistantWaterproofWaterproof
Price per Month (Based on a Small Sized Dog)$18.68$18.52
Minimum Age Requirement8 Weeks8 Weeks

Side Effects

All medications have side effects, and flea and tick treatments are not exempt.

These are the most common side effects for Credelio and NexGard:


  • Weight loss
  • Elevated blood urea nitrogen
  • Increased urination
  • Diarrhea
  • Seizures


  • Vomiting
  • Diarrhea
  • Lethargy
  • Loss of appetite
  • Itching
  • Seizures
Note: Both Credelio and NexGard use active ingredients in the isoxazoline class of drugs, which has been documented to cause adverse neurological reactions such as seizures, tremors, and lack of coordination[5].

Additionally, it is advised to use caution with dogs with a history of seizure activity when using isoxazoline class medications.

Which is Safest?

Winner: NexGard

They are about the same, and though the side effects are similar, Credelio lists elevated blood urea nitrogen, which impacts the kidneys’ function.

Which Works Fastest?

Winner: Credelio

Credelio states that it starts working to kill flea and ticks in just four hours.

NexGard does not state how long it takes for it to kill ticks, though it is only four hours for fleas.

Which is the Cheapest?

Winner: Credelio

Credelio is cheaper than NexGard by about sixteen cents, so they are pretty much the same per month.

Which Lasts Longer?

Winner: Tie

They are both listed to last 30 days.

Overall Winner

Winner: NexGard

NexGard protects against more parasites, has fewer allergens, and is the only FDA approved tick preventative that protects against Lyme Disease.

Standout Features

Though the two medications are very comparable, there are a couple of small differences that set them apart from one another:

  • NexGard kills more parasites and is more allergy-friendly.
  • Credelio kills ticks in less time than many other tick preventatives.
Interested in another comparison? Check out NexGard vs Frontline!


The two products are very much alike.

Though, NexGard is a product I have confidently used with my puppy Mira.

It is safe, and it helped take care of her demodectic mange when she was around 12 weeks old, which is why I am partial to this product.

However, even if I hadn’t used it for Mira, I would still pick NexGard over Credelio for the slight differences in ingredients, side effects, and its protection against Lyme Disease.

Use NexGard If:

  • Your dog has food allergies such as pork, wheat, barley, or lactose
  • Your dog has issues with mites
  • Your dog has kidney issues

Use Credelio If:

  • You need a fast acting flea and tick preventative


Can I Use NexGard and Credelio Together?

Though they do not use the same active ingredient, both parasiticides are in the isoxazoline class of drugs, so it is not recommended to use the two together.

Which is More Effective Against Fleas, NexGard or Credelio?

The two are about the same.

They both start killing fleas in just four hours.


Credelio vs Nexgard Flea Medications - Pinterest

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