The 5 best cat dewormers of 2024

A broad-spectrum dewormer can knock out multiple types of parasites at the same time. We recommend Bayer Drontal Broad Spectrum Dewormer because it is safe, effective, and eliminates all parasites within seven days. No other cat dewormer kills as many different types of worms as Drontal. This dewormer features two powerful active ingredients, pyrantel pamoate and praziquantel, which together cover tapeworms, hookworms, and roundworms.

To give your cat this medicine, place the tablet far back in their mouth until they swallow it or crumble and mix it into a small amount of wet food. Drontal has a very low risk for side effects and is safe for kittens and cats more than 8 weeks old and ranging from 2 to 16 pounds.

Bayer Drontal Broad Spectrum Dewormer requires a prescription from your veterinarian. Don't skip this step because cats may have other parasites that even broad-spectrum dewormers can't eliminate.

When using a broad-spectrum dewormer like Drontal, your cat may require one or more follow-up treatments to make sure all the worms are eliminated. If your cat has fleas, you should also use one of the best flea treatments for cats to prevent future tapeworm infections.

Droncit Tablets tackle tapeworm infestations quickly and safely in cats and kittens 6 weeks of age and older. They are conveniently sold per pill, unlike the other tapeworm dewormer we considered, Bayer Tapeworm Dewormer Tablets, which are sold in a three-pack and at a slightly higher cost per pill.

Each tablet contains 23 milligrams of the active ingredient praziquantel, which works to paralyze and eliminate tapeworms within 24 hours. This ingredient is effective against the most common species of tapeworms (Dipylidium caninum and Taenia taeniaeformis), eliminating them in a single dose. You can feed the tablet to your cat whole or crumbled and mixed with food.

Because cats can become reinfected by ingesting another flea, effectively eliminating tapeworms requires treating your cat for fleas as well.

Centragard quickly and safely treats tapeworms and two other intestinal parasites (hookworms and roundworms) in cats and kittens 7 weeks of age and older. It is a great option for cats that won't take pills. Simply squeeze the liquid in one spot on the back of your cat's neck and allow it to dry. You can use Centragard one time to treat an infestation of tapeworms, hookworms, or roundworms, or give it monthly to keep your cat free from intestinal parasites and also prevent deadly heartworms.

Centragard contains the active ingredients eprinomectin and praziquantel, which work to kill worms and prevent future infections. These ingredients are effective against the two most common species of tapeworms (Dipylidium caninum and Taenia taeniaeformis), two species of hookworms (Ancylostoma tubaeforme and Ancylostoma braziliense), one species of roundworm (Toxocara cati), and heartworms.

Because cats can become reinfected by ingesting another flea, effectively eliminating tapeworms requires treating your cat for fleas as well.

Interceptor is a great choice for pet owners who wish to give an oral preventive rather than a topical product because of the many parasites it protects against. In addition to preventing deadly heartworm disease, Interceptor Flavor Tabs treat and control roundworms, adult hookworms, and adult whipworms with the active ingredient milbemycin oxime. Each pill protects for 30 days, and it's safe for kittens as young as 6 weeks of age.

Interceptor is one of only two chewable parasite preventives available for cats, Heartgard being the other option. Unlike Interceptor, Heartgard only treats and controls one other parasite (hookworms) in addition to heartworms.

You can give your cat an Interceptor Flavor Tab as a treat or hide it in a small amount of wet food. You'll need a prescription from your veterinarian to purchase Interceptor. As with all heartworm medications, your cat needs a heartworm test prior to starting this preventive and once a year thereafter.

Our pick for best topical parasite preventive is Revolution Plus Topical Solution because it protects cats against six different parasites — more than any other topical preventive. Revolution Plus beat out the other topical preventive we considered, Bravecto Plus Topical Solution, because it is safe for kittens 8 weeks and older. Bravecto cannot be used for kittens younger than 6 months old. Revolution Plus also kills ear mites, while Bravecto does not.

Revolution Plus treats and controls two intestinal worms: roundworms and hookworms. It also prevents heartworms, treats and prevents flea infestations (killing adult fleas before they can lay eggs), and treats and controls ear mites and three different tick species (black-legged or deer tick, Gulf Coast tick, and American dog tick). It does not kill tapeworms.

Given every 30 days, this monthly spot-on treatment is simple to apply in one spot to your cat's skin between the shoulder blades. The medication, a small amount of liquid, is absorbed through the skin and dries quickly, leaving nothing behind. Unlike some other topical products like Advantage Multi and Bravecto, you do not need to wear gloves to apply Revolution Plus and you can touch your cat after application, even if the product has not completely dried. If you get the medication on your hands, simply wash them with soap and water.

Before choosing a broad-spectrum parasite preventive for your cat, have a conversation with your veterinarian who can advise you on what might be best depending on your cat's lifestyle and what parasites are most common in your area.

You must obtain a prescription from your veterinarian to purchase Revolution Plus. As with all heartworm medications, your cat needs a heartworm test prior to starting this medication and once every year after. Revolution Plus should be used with caution in cats with a history of neurologic disorders such as seizures.

It's important to take your cat to the vet before giving them a dewormer. If you suspect your cat has worms, always take them to the veterinarian for a physical exam and fecal test, which is an examination of the stool that reveals what type of worms your cat has.

"Generally speaking, if they have one parasite, they'll have multiple parasites," says Dr. Herman Jeffer, a veterinarian at Cornwallis Road Veterinary Hospital. "If they have roundworms, it's not uncommon to see tapeworms or other worms as well, or 'non-worms' like coccidia."

Certain single-celled microscopic parasites (protozoa), including coccidia and Giardia, cause symptoms similar to those caused by intestinal parasites, but they are not true worms. They require different prescription medications to treat them — dewormers won't help.

Even though some dewormers do not require a prescription, do not skip the vet visit since different drugs treat different worms. Your vet can also determine if your cat may have other health issues that need to be addressed.

"It's important to see your veterinarian so they can identify what parasites are present and then prescribe the appropriate deworming medication," says Dr. Colleen Sawyer, a veterinarian with Rolesville Veterinary Hospital. "Your vet can also explain any risks for human disease, which is also parasite dependent."

Depending on the type of worms found, your cat might also need follow-up deworming and a follow-up fecal exam to make sure no parasites remain. Your veterinarian can also identify any other health issues that might be going on aside from intestinal parasites.

My knowledge about intestinal parasites and their treatment and prevention is informed by a 20-year career writing and editing for pet and veterinary publications. I also worked as an assistant in veterinary hospitals for eight years, where one of her jobs was conducting fecal tests to look for the presence of worms. 

For this guide to the best cat dewormers, I consulted two veterinarians for advice regarding the treatment and prevention of intestinal parasites like tapeworms, roundworms, and hookworms, as well as heartworms and ectoparasites like fleas, ticks, and mites. Although this information guided our product selection, our experts did not specifically endorse any of the products included in this guide. I also used the quick product reference guide published by the independent, nonprofit Companion Animal Parasite Council. It lists all FDA- and EPA-approved parasite control products for small animals, including each product's active ingredients and uses.

Here are the main attributes I looked for:

Safety and efficacy: I only considered FDA- or EPA-approved dewormers and preventives for this guide. We then consulted the Merck Veterinary Manual to ensure all ingredients in these products are known to be safe and effective for use in cats and kittens.

Number of parasites treated: In general, the more parasites a preventive product covers, the higher it was rated. 

Ease of use: Products were rated lower if they were more complicated to use than a similar product. For instance, products ranked lower if the pet owner must wear gloves to apply the product or if children and pets need to be kept away from the treated animal for a specified amount of time.

What is the best cat dewormer?

In general, Sawyer prioritizes products that provide both flea and heartworm prevention. "Heartworm disease, although rare, is not treatable in cats and has a high fatality rate," she says. "Coverage for ticks, immature life stages of fleas, and intestinal parasites are also important, and fortunately now there are products available that protect against all the above."

Are natural dewormers better for cats?

Jeffer says he has serious doubts about whether natural deworming products are effective. He points out that conventional, veterinarian-recommended dewormers are not only very effective but extremely safe to use. "They've all been used over decades, and there are very few to no side effects associated with them," he says.

Can indoor cats get worms?

Outdoor cats are most at risk of picking up intestinal parasites like roundworms and hookworms, as well as heartworms, fleas, and ticks. However, even indoor cats need parasite prevention. Fleas can be brought into the house by other pets or even on your clothing, and cats that live inside can still be exposed to other parasites. Jeffer says heartworms are the main risk for indoor cats. "Even one heartworm can potentially be fatal to a cat," he says. "Even if a couple of mosquitoes get into the house that happen to be carriers for heartworm disease, there's a chance that an indoor-only cat can get heartworms and can actually die from it."

Should you give cats parasite prevention medicine year-round?

Veterinarians recommend broad-spectrum parasite prevention for all cats. Some owners think their cats only need preventives in the spring and summer, but veterinarians recommend keeping cats on a broad-spectrum parasite preventive all 12 months of the year. Different parasites are active during different months, and parasite activity can vary depending on where you live. Additionally, parasites can become active earlier than expected, including in the winter. "It's a little bit of a gamble, especially with climate change and the unpredictability of the weather in most areas of the country," Jeffer says. 

Indoor-outdoor cats are at high risk for contracting intestinal parasites like roundworms, hookworms, and whipworms, and all cats, including those that live indoors, need prevention from deadly heartworms. Sawyer says parasites can find their way into your home in many different ways. This includes other animals like the family dog or small rodents. Humans can also bring fleas inside on their clothing or shoes, and mosquitoes that transmit heartworm disease can easily enter through open doors or windows. 

Cornell University veterinarians estimate that as many as 45% of cats have intestinal parasites at any given time. In adult cats, parasite infestations may cause mild to moderate digestive symptoms like vomiting, diarrhea, and gas. However, heavy infestations, especially in kittens, can lead to more severe digestive symptoms, weight loss, anemia, malnutrition, and restricted growth.

"We'll see cats coming in, for example, if they've been in a feral situation. They are anemic, bloated, they have chronic diarrhea and vomiting, their coats are brittle and unkempt, and they can be very depressed," Jeffer said. "Kittens can actually die from parasite infestations."

Some of the most common worms seen in cats are roundworms, tapeworms, and hookworms.

Roundworms: Common in cats, especially in kittens, roundworms are large (3 to 6 inches), smooth, and round-bodied. You might not notice symptoms, particularly if your cat has only a few roundworms. In kittens, large numbers of worms may cause a pot-bellied appearance, vomiting, diarrhea, low appetite, dull coat, and restricted growth. You might also see roundworms in your cat's stool or vomit.

Tapeworms: If you see something in your cat's feces that resembles grains of white rice, or you notice them licking or biting the area under their tail, they could have a tapeworm infestation. Cats contract tapeworms when they ingest an infected adult flea. As the tapeworm grows, segments break off and pass in your cat's stool.

"Probably the most common kind of worm that pet owners are going to notice is a tapeworm," Jeffers says. "The cat might have other ailments that need to be addressed, so there are a lot of reasons to bring your cat to the vet to sort out which worm it is and to make sure there aren't secondary issues that are resulting from that infection."

Hookworms: Tiny worms nearly invisible without the assistance of a microscope, hookworms are blood-sucking parasites that attach to the wall of the intestines. Signs of hookworm infection in cats include anemia, weight loss, and dull coat. Hookworm-infested cats also sometimes have dark, tarry-looking stools.