10 Best Flea Sprays 2025 in the United States

Frontline Plus Flea and Tick Treatment for Small Dogs is a trusted product for dogs weighing 5 to 22 lbs. It effectively breaks the flea life cycle using active ingredients fipronil and (S)-methoprene, targeting adult fleas, eggs, larvae, and ticks that can transmit Lyme disease. This treatment is suitable for use on puppies as young as eight weeks old and promises a 30-day protection with each monthly dose.

Its waterproof formula ensures that it remains effective even after your dog gets wet, making it a convenient choice for active pets. The application process requires careful handling to avoid contact with the skin and ensure proper placement between the shoulder blades. While generally safe, it is crucial to follow the instructions to prevent ingestion or misuse. Some users may find the orange scent noticeable, though it typically dissipates after application.

Additionally, being a topical treatment, it may not be suitable for dogs with sensitive skin or those prone to allergies.

FRONTLINE Plus Flea and Tick Treatment is designed for large dogs between 45 and 88 pounds. It contains two active ingredients, fipronil and (S)-methoprene, which work together to kill adult fleas, flea eggs, and larvae, helping to break the flea life cycle and protect your dog for a full month. This product also targets ticks, including those that can carry Lyme disease, making it a solid choice if you want broad parasite control. It’s waterproof and fast-acting, so your dog stays protected even after swimming or bathing. The treatment is applied topically in one easy step by parting the hair on your dog’s back and applying the liquid directly on the skin, which many users find straightforward and convenient. It’s unscented, so it won’t bother pets or people sensitive to smells.

Safety-wise, FRONTLINE Plus can be used on puppies as young as eight weeks old, but it’s important to apply the correct dose only once a month and avoid contact with the treated area until it dries. Some owners might find the packaging a bit fiddly, as you need scissors to open each applicator. Trusted and popular for over 20 years, this product is suitable for dog owners looking for a reliable, monthly flea and tick treatment that covers all life stages of fleas and provides ongoing protection with minimal hassle.

Frontline Plus Flea and Tick Treatment for Cats is designed to offer long-lasting and effective protection against fleas and ticks. The active ingredients, fipronil and (S)-methoprene, work well to not only kill adult fleas but also break the flea life cycle by targeting eggs and larvae. This makes it a good choice for preventing future infestations. The product is waterproof and provides protection for up to 30 days with each application, which can be very convenient for pet owners.

It's also safe for kittens over 8 weeks old and cats that weigh over 1.5 lbs, making it versatile for a wide range of cats and kittens. Users will appreciate that it doesn’t have a strong odor as it is unscented, which can make the application process more pleasant for both the pet and the owner. The application process is straightforward, involving a simple topical treatment to the back of the cat's neck.

One downside could be the necessity of handling the product carefully to avoid the cat ingesting it or coming into contact with the treated area until it’s dry, which might require some monitoring. This product has been trusted by pet owners for over 20 years. It’s important to follow the instructions carefully to ensure the safety and effectiveness of the treatment. For those with both cats and dogs, there is also a formula available for dogs, making it easier to manage pet care within a household.