Revolution for Cats: Flea, Heartworm, and Ear Mite Prevention

If you have an indoor cat and you've been told she doesn't need parasite prevention, I understand the logic. She never goes outside, so how would she get fleas or heartworms? The problem is that logic doesn't hold up in Cypress, TX. Fleas hitch rides on your shoes, your dog, and even through screen doors. Mosquitoes get inside. And once heartworms infect a cat, we have no approved treatment to kill them. At Hearthstone Animal Clinic, I recommend Revolution for most of my feline patients because it covers the parasites I actually see causing problems here in southeast Texas.

What is Revolution and how does it work?

Revolution (selamectin) is a topical medication you apply once a month to the skin at the base of your cat's skull. It absorbs through the skin and enters the bloodstream, where it distributes to the skin, tissues, and intestinal tract. Selamectin works by disrupting nerve transmission in parasites, which paralyzes and kills them while remaining safe for mammals.

One application protects against:

• Fleas (kills adult fleas and prevents eggs from hatching)
• Heartworms (kills the larval stage before they reach the heart)
• Ear mites (Otodectes cynotis)
• Roundworms and hookworms (intestinal parasites)

That's a lot of coverage from a single product. For cats, this kind of broad-spectrum protection in one application matters because, let's be honest, most cats don't cooperate for multiple treatments.

Does my indoor cat really need heartworm prevention?

This is the question I get most often, and I understand why. It seems excessive to medicate a cat who never sets foot outside. But here's what changes that calculation: Texas ranks among the highest states in the country for heartworm disease, and the American Heartworm Society reports that up to 25% of heartworm-positive cats are classified as indoor-only by their owners.

Mosquitoes don't need an invitation. They slip through doors, ride in on people, and breed in standing water that's everywhere in our humid climate. One infected mosquito bite is all it takes. And here's the part that makes feline heartworm so concerning: there is no approved drug to kill adult heartworms in cats. In dogs, we have a treatment protocol. In cats, we can only manage symptoms and hope the cat outlives the worms, which take 2 to 3 years to die naturally. Some cats don't make it. Some develop permanent lung damage. Prevention is the only real protection we have.

What heartworm disease looks like in cats

Cats don't present like dogs. You won't see the classic cough and exercise intolerance. Instead, I see vomiting (often misdiagnosed as hairballs), difficulty breathing, or sudden collapse. Some cats die without any warning signs. Even a small worm burden, sometimes just one or two worms, can be fatal because a cat's heart and lungs are so much smaller than a dog's.

How effective is Revolution against fleas?

Revolution kills adult fleas within 36 hours of application and prevents flea eggs from hatching for a full month. For most cats in my practice, this provides solid protection. I do see some flea breakthrough in heavily infested environments, especially in late summer when flea populations peak in Cypress. In those cases, we may need to add environmental treatment or temporarily switch to a faster-acting oral product.

The bigger point is this: Revolution prevents infestations from getting established. If you're applying it consistently every month, you're unlikely to ever deal with a serious flea problem. If you're reading this because your cat already has fleas and you've been inconsistent with prevention, that's fixable. Start now, treat the environment, and stay consistent going forward.

What about ear mites?

Ear mites (Otodectes cynotis) are extremely common in kittens and cats acquired from shelters, rescues, or multicat environments. They cause intense itching, dark crumbly discharge in the ears, and head shaking. I can usually spot them on an ear swab under the microscope in about 30 seconds.

Revolution is highly effective against ear mites. One or two monthly doses typically clears an active infestation, and continued monthly use prevents reinfection. This is particularly useful in households with multiple cats, where ear mites spread easily between animals.

How much does Revolution cost?

At Hearthstone Animal Clinic, a single dose of Revolution for cats runs roughly $18 to $25 depending on your cat's weight. A six-month supply typically costs $100 to $140. We also carry Imoxi, which is a generic equivalent of Revolution Plus and offers the same active ingredients at a lower price point for owners who want to save money without sacrificing protection.

For context, treating a flea infestation (exam, medications, possibly follow-up visits) easily exceeds $150. Managing heartworm disease in a cat, with the chest X-rays, echocardiograms, and supportive care it requires, can run into the thousands with no guarantee of a good outcome. Prevention is genuinely the cheaper option here.

Is there a generic version?

Yes. Imoxi is the generic topical we carry, and it contains the same active ingredient (selamectin) as Revolution. Some formulations add sarolaner for broader flea and tick coverage, similar to Revolution Plus. I'm comfortable recommending either, and I'll tell you which makes more sense based on your cat's lifestyle and risk factors.

Are there side effects I should watch for?

Revolution has been on the market since 1999 and has an excellent safety profile. Most cats tolerate it without any issues. The most common side effects I see are:

• Temporary hair loss at the application site (rare, usually grows back)
• Mild skin irritation where the product was applied
• Hypersalivation if the cat grooms the application site before it dries

Serious reactions are uncommon. If your cat vomits, has diarrhea, or seems lethargic after application, contact us. Revolution is safe for kittens 8 weeks and older and weighing at least 2.6 pounds. It's also safe for pregnant and lactating queens, which makes it one of the more versatile options we have.

How does Revolution compare to other options?

The main alternatives for cats are oral flea preventives (like Comfortis) or different topical combinations. Here's how I think about it:

• Revolution or Imoxi: Best all-around choice for most cats. Covers fleas, heartworms, ear mites, and intestinal parasites. Topical application works well for cats who won't take pills.
• Oral flea preventives: Kill fleas faster (often within hours) but don't cover heartworms. You'd need to add a separate heartworm preventive.
• Topicals without heartworm coverage: Fine if your cat is truly zero-risk for mosquito exposure, but I have trouble recommending this approach in southeast Texas.

If this were my cat, I'd use Revolution or Imoxi year-round. The heartworm protection alone justifies it, and the flea and ear mite coverage is a bonus.

When should you talk to your veterinarian?

Bring up parasite prevention at any wellness visit, or sooner if you notice:

• Scratching, hair loss, or tiny black specks in the fur (flea dirt)
• Dark, crumbly debris in the ears with head shaking
• Coughing, wheezing, or vomiting that looks like hairballs but happens frequently
• Any new cat or kitten entering your household

If you've adopted a kitten or rescue cat, getting them on prevention early is one of the best things you can do. Many of these cats arrive with active flea or ear mite infestations, and starting Revolution immediately prevents those problems from spreading to your other pets or your home. You can check our full list of services to see what else we cover during wellness exams, or review our transparent pricing so you know what to expect.

Get your cat protected in Cypress

If you're not sure whether your cat needs parasite prevention, or you've been meaning to start but haven't gotten around to it, now is a good time. Heartworm, flea, and ear mite prevention is straightforward, affordable, and genuinely protective. If you're in Cypress, TX and want to discuss the right approach for your cat, schedule a visit at Hearthstone Animal Clinic or call us at (281) 859-9244. We'll figure out the best fit for your cat's age, weight, and lifestyle, and get her started on protection that actually makes sense for our area.