Best Flea Medicine for Cats, According to Vets

By: Sarah Wooten, DVM

A critical part of pet care is ensuring that your cat is free of parasites inside and outside. Fleas are one of the most common external parasites seen on cats. Fleas not only cause itching and irritation to cats, they can carry other infectious organisms like tapeworms and cause serious health problems like anemia. In addition, fleas are a human health concern, as they spread diseases like plague, typhus, and cat scratch disease.

Fortunately, there are several options when it comes to flea control and eradication that can keep fleas off your pet and out of your life. This guide is intended to help cat owners choose the best flea medicine for cats based on their lifestyle and needs.

Why Flea Treatment Is Essential for Cats

Fleas are tiny insects that are red-brown in color and about the size of a pin. They jump onto cats and feed by biting and sucking blood. While one flea is generally not a problem for most cats, the problem is that fleas reproduce quickly. With one female flea capable of laying up to 50 eggs a day, one flea can quickly become a huge flea infestation! Flea prevention is key, as flea infestations can be difficult to eliminate once established.

The rapid reproduction cycle of fleas typically results in a massive flea problem very quickly that not only affects the cats in your household but also dogs and other mammals, including humans! Additional reasons that flea control is a critical part of cat health care include:

Itching and Allergies. Some cats have allergies to flea saliva, and one bite from one flea can make the cat so itchy that they tear their own hair out. In addition, cats with flea allergy develop skin infections and crusty bumps all over their body called miliary dermatitis even in areas they don’t scratch.  Even if a cat doesn’t have a flea allergy, being bitten by fleas can still make them miserable.

Anemia. Cats with heavy flea infestations or kittens with fleas can lose so much blood to the fleas that they can develop anemia, otherwise known as a low red blood cell count. Anemia makes cats feel tired and weak and is hard on the cardiovascular system.

Flea-borne Diseases. Fleas not only suck blood, but they carry other infectious diseases that can infect cats and humans alike. Flea-borne diseases that affect cats and humans include tapeworms and bartonellosis which is responsible for cat scratch disease.

What to Look for in the Best Flea Medicine for Cats

With so many flea products on the market it can be difficult for cat owners to find the best treatment for their cat. The following are some general recommendations of what to look for when shopping for the best flea medicine for your cat.

• Effectiveness: Look for flea medicine that is labeled to eliminate adult fleas, eggs, and larvae. This is necessary to break the flea life cycle so no new fleas emerge to terrorize your pet. Sometimes, your vet will recommend a combination of products to cover all your bases, such as a parasiticide that kills fleas, eggs, and larvae as well as an insect growth regulator to stop eggs from hatching.
• Application Method: Flea control comes in many different forms. There are topical treatments, oral medications, flea collars, sprays, powders, shampoos and more.
• Safety: While there are many flea control products available, not all are equal in safety or effectiveness. In addition, some over-the-counter and prescription strength flea control products labeled for use in dogs are not approved for use in cats because they are toxic to cats. When shopping for flea control, it is important to read the labels and know if the product is safe for cats. Even better, ask your veterinarian for safe products recommendations and only use products that are vet-approved and safe for kittens, senior cats, and pregnant cats.
• Longevity: Flea control products range in how long they kill or prevent fleas. Some products only last a day or two, other products last a few weeks to a month, and some products last even longer than that. Determine what your cat needs in terms of longevity of flea control when shopping for flea control products.
• Additional Benefits: Some prescription strength flea treatments also prevent ticks, ear mites, heartworms, and other internal parasites, ensuring that your cat is protected inside and out. These products are typically only available through your local veterinarian or with a prescription to purchase online.
• Environmental Treatment: An important part of eradicating fleas if you have a flea problem is not only treating the pets in the house but also treating the environment. Look for products that are vet recommended and tested for safety and efficacy.

The Best Flea Medicines for Cats

Bravecto Plus for Cats – Best Overall

Shop Bravecto

• Key Features:
  • Provides comprehensive internal and external parasite control and is labeled to kill fleas, several species of ticks, heartworms, roundworms, and hookworms
  • Provides parasite protection for up to 12 weeks
  • Fast acting, safe, effective, and FDA approved for use in cats
• Why it’s great for cats: Highly effective, safe, easy to apply to skin, comprehensive parasite protection that lasts 2 times longer than most other flea treatments on the market.
• Things to consider: Not recommended for cats under 6 months of age or cats weighing less than 2.6 pounds.

Seresto for Cats – Best Flea Collar

Shop Seresto

• Key Features:
  • kills and repels fleas and ticks for eight continuous months
  • Odorless and non-greasy
  • No prescription required
• Why it’s great for cats: Seresto collars are recommended by veterinarians and provide continual flea and tick protection for months, are easy to use, and are generally well tolerated by most cats.
• Things to consider: Not for use in cats younger than 10 weeks of age.

Knockout E.S. Area Treatment – Best for Treating the Environment

Shop Knockout

• Key Features:
  • Kills active flea infestations and ticks in the indoor environment
  • Prevents flea infestations from developing and prevents re-infestations of fleas for 7 months
  • Safe for use on rugs, carpets, upholstered furniture, pet beds, and pet resting areas
• Why it’s great: Kills fleas and ticks in the environment and prevents reinfestation of the environment for 7 months.
• Things to consider: Harmful if absorbed through the skin, avoid contact and wash hands after use. Pets should be vacated from the area that is being treated until the product has fully dried, usually about 2 hours after application.

How We Chose the Best Flea Medicine for Cats

Products chosen to be the best flea medicine for cats were evaluated using several criteria, including:

• Prioritizing products that have proven clinical effectiveness and high safety ratings.
• Products that have been shown to be effective in eliminating fleas for many years.
• Ease of use
• Affordability
• Longevity of effectiveness
• Rate of kill prioritizing products that killed fleas faster
• Including products that included several benefits, such as providing protection against pests other than fleas

Our Take on Flea Medicine for Cats

• To be effective, flea prevention should be used year-round on all cats and dogs in the household, especially in warm climates.
• Not all flea products are recommended for all cats. Before starting any new flea treatment, consult with your veterinarian to make sure the treatment is safe and effective for your cat.
• If you have had a flea infestation, it is very important to remember that flea larvae and eggs live in the environment. To fully eradicate fleas, treat all pets in the household (even if they are indoor only) and the environment.

Author Bio:

Dr. Sarah Wooten is an international influencer in the veterinary and animal health care spaces. She has 16 years experience in private practice and over 10 years experience in veterinary media work, and is a certified veterinary journalist. She is also passionate about helping pet parents learn and has written thousands of articles and filmed hundreds of videos about pet care and the human-animal bond for outlets such as DVM360.