PetArmor Plus vs Frontline Plus: Which Flea Treatment is Better?

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PetArmor Plus and Frontline Plus may appear to be the same thing with the same active ingredients; however, on closer inspection, there are few differences worth noting.

Both PetArmor Plus and Frontline Plus have been proven to be safe and effective topical flea and tick treatments. And both products last a whole month.

To reduce the wordiness of this PetArmor vs Frontline review, I will drop the word “Plus” from their names.

Still, PetArmor Plus and Frontline Plus are the products I am explicitly referring to unless otherwise specified.

PetArmor Plus

  • Active Ingredients:  Fipronil and (S)-methoprene
  • Type: Topical
  • Duration: 1 Month

PetArmor is part of the Pet IQ company.

Pet IQ, founded in 2010, is located in Eagle, ID. Pet IQ not only creates pet care products but also has vet hospitals and mobile vet clinics. Pet IQ is planning on opening more than 1,000 vet brick and mortar hospitals by 2023[1].

There are several dog products under the PetArmor name, such as deworming medicine, skin and coat care, ear care, and joint health supplements.

Plus, the PetArmor brand has several affordable flea and tick products, including four different topical treatments, two all-natural products, flea and tick collars, and sprays.

PetArmor Plus’s two active ingredients, fipronil and (S)-methoprene, work to kill fleas, flea eggs, flea larvae, ticks, and chewing lice.

This topical treatment is waterproof and lasts up to 30 days.

PetArmor is applied directly to the skin between your dog’s shoulder blades. This topical treatment starts working in 24-48 hours.

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After 24 hours from applying PetArmor your dog is free to swim or be bathed.

PetArmor spreads from the shoulder blades to cover the whole body.

And when fleas, ticks, and lice land on your dog and come in contact with PetArmor through the dog’s coat, they are killed before they bite your dog.


  • Works to kill fleas, ticks, and chewing lice
  • Easy to apply
  • Waterproof
  • Affordable


  • Takes longer to start working
  • Does not act as a repellent

Be sure to check out our PetArmor Plus Review!

Frontline Plus

  • Active Ingredients: Fipronil and (S)-methoprene
  • Type: Topical
  • Duration: 1 Month

Frontline is a Boehringer Ingelheim & Merial Group flea and tick product that has been a market leader for more than twenty years. The Merial Group is a US-based company that was founded in 1981.

Frontline Plus is the second version of this product, which hit the market in 2000.

Though Frontline Plus contains much of the same ingredients as the original version, the Plus has active ingredient s-methoprene.

S-methoprene is an insect growth regulator and helps to break the flea life cycle[2].

Frontline’s other active ingredient is fipronil, which is responsible for killing fleas and ticks by disrupting their nervous system[3].

Frontline Plus is applied topically, which then spreads over the dog’s body, where it is stored in oil glands in your dog’s skin. Once fleas and ticks come in contact with Frontline Plus, it kills these parasites.

In addition to fleas and kills, Frontline Plus is also effective at killing chewing lice.

The biggest drawback to Frontline is that it does not work as a repellent to fleas, ticks, and lice. However, unlike other flea and tick treatments, parasites don’t need to bite your dog for it to work on the flip side.


  • Fleas and ticks are killed on contact
  • Waterproof
  • Fast-acting starts working in just 4 hours
  • Few side effects


  • Dogs with sensitive skin may be prone skin irritation
  • Does not repel fleas and ticks

Don’t forget to read our full Frontline Plus review!

PetArmor vs Frontline: Head to Head Comparison

FormTopical Topical 
Kills Fleas and TicksYesYes
Repels Fleas and TicksNoNo
Other ParasitesChewing LiceChewing Lice
Active IngredientFipronil and       (S)-methopreneFipronil and       (S)-methoprene
Duration1 Month1 Month
Prescription NeededNoNo
Waterproof or Water ResistantWaterproofWaterproof
Price per Month (Based on a Small Sized Dog)$6.59$11.33
Minimum Age Requirement8 Weeks8 Weeks

Side Effects

PetArmor Plus

  • Skin irritation such as redness or itchiness

Frontline Plus

  • Irritation at the application site
PetArmor vs Fontline side effect which flea treatment is better

Which Flea Treatment is Better?

Which is Safest?

Winner: Tie

Since PetArmor and Frontline both have the same active ingredients in the same quantities, the side effects are the same.

I have been using Frontline Plus on my dogs since it was released in 2000 and (knock on wood) have never had any issues with it.

Both products are relatively safe, with fewer side effects than many other flea and tick products.

Which Works Fastest?

Winner: Frontline

Frontline starts working just 4 hours, whereas PetArmor takes 24-48 hours.

Which is the Cheapest?

Winner: PetArmor

PetArmor is significantly less expensive than Frontline.

Which Lasts Longer?

Winner: Tie

The two products both provide 30 days of protection against fleas, ticks, and chewing lice.

Standout Features

Both products use the same active ingredients that kill parasites on contact, helping keep your dog safe, but there are two differences:

  • PetArmor is less expensive.
  • Frontline works significantly faster than PetArmor.

Overall Winner: Frontline

Though Frontline Plus is more expensive than PetArmor Plus, Frontline starts working 20 hours faster than PetArmor.


PetArmor and Frontline are so much alike that both are an excellent choice. They are both waterproof, safe enough for puppies as young as 8-weeks, and both have minimal side effects.

However, the two products’ inactive ingredients are different, which accounts for the two main differences in the flea and tick treatments.

The inactive ingredients make each of them uniquely beneficial in specific situations, like:

  • If you are looking for an economically effective flea and tick treatment, then PetArmor Plus is the one you will want to choose.
  • If you need a product that will start working in just four hours, then Frontline Plus is the right choice.


Do PetArmor Plus and Frontline Plus Work against Mosquitos?

No, neither products work to kill or repel mosquitos.

However, PetArmor Max works against fleas, ticks, and mosquitos.

Can You Use PetArmor Plus and Frontline Plus Together?

No, the two products have the same active ingredients and may cause significant skin irritation when combined.

Are There Any Differences between PetArmor Plus and Frontline Plus?

Besides pricing, the most significant difference between the two flea and tick treatments is that Frontline Plus works faster than PetArmor Plus.


Pet Armor Plus vs Frontline Plus Flea Treatment for Dogs Pinterest

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