During my time as a veterinary assistant, I regularly performed fecal tests to screen cats for worms. These intestinal parasites live hidden inside your cat, silently causing harm. Fortunately, the best cat dewormers and parasite preventives can quickly eliminate infections such as tapeworms, hookworms, and roundworms and prevent their return.

There are many types of cat dewormers available, including oral and topical treatments. Some products eliminate active parasite infections but don’t prevent new ones, while others treat worms and provide ongoing monthly prevention.

Because different medications target different parasites, your veterinarian will need to perform a fecal test before you can deworm your cat. They will be able to identify the type of worm your cat has and recommend the appropriate treatment, such as a prescription dewormer highlighted in this guide.

To determine the best deworming medications, I consulted veterinarians about how they diagnose and treat worms in cats. I then evaluated products based on safety, effectiveness, parasite coverage, and ease of use.

Read more about how Business Insider Reviews tests and researches pet products.

Our top picks for the best cat dewormers

Best broad-spectrum dewormer: Profender Topical Solution – From $16 per dose at Chewy

Best tapeworm dewormer: Droncit Tablets – $5 per tablet at Chewy

Best topical for deworming and prevention: NexGard Combo – From $30 per dose at Chewy

Best tablet for deworming and prevention: Interceptor Flavor Tabs (6-month supply) – From $57 at Chewy

Best broad-spectrum

No other cat dewormer kills as many types of worms with a single dose as Profender does. It is a broad-spectrum dewormer, which means it eliminates multiple types of intestinal parasites at once. The topical dewormer contains two powerful active ingredients, emodepside and praziquantel, which eliminate the two most common species of tapeworms, one type of hookworm, and one type of roundworm.

Aside from its effectiveness, it is easy to use. To give your cat Profender, part the hair at the base of your cat’s head and apply the solution directly to the skin. After application, keep your cat separated from other pets in the household until the solution has dried. If you’d like to give a pill instead, Drontal is our former top pick in this category, but it often requires a follow-up dose.

Profender is available by prescription only, so you’ll need to consult your veterinarian before using it. This step is important, as your cat may have other parasites that even broad-spectrum dewormers won’t eliminate.

Best for tapeworms

Droncit tablets quickly and safely tackle tapeworm infestations in cats and kittens over 6 weeks old. You can give the tablet whole or crush it and mix it into your cat’s food.

It’s effective against the two most common tapeworm species and eliminates them with a single dose. Cats primarily become infected with tapeworms when they ingest fleas infected with tapeworm larvae. Droncit tablets contain praziquantel, an active ingredient that paralyzes and eliminates tapeworms within 24 hours.

It’s a very affordable treatment option. Unlike the other tapeworm dewormer I considered, Elanco Tapeworm Dewormer, Droncit is conveniently available as single tablets, while Elanco is sold in a three-pack and at a slightly higher cost per pill.

To prevent further infections, you’ll also need to treat your cat for fleas. For this reason, your vet may also recommend monthly flea prevention with NexGard Combo or another of the best flea and tick treatments for cats.

Best topical for deworming and prevention

NexGard Combo kills worms and other parasites with a single topical treatment. You can use it to treat an infestation of tapeworms, hookworms, or roundworms.

It can also be given monthly to keep your cat free from intestinal parasites, fleas, and ticks, and prevent deadly heartworms. In general, Dr. Colleen Sawyer, a veterinarian with Rolesville Veterinary Hospital, 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 said. “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.”

It is also an excellent option for cats who won’t take pills. Just squeeze the liquid onto one spot on the back of your cat’s neck and let it dry.

NexGard Combo contains three active ingredients: eprinomectin, praziquantel, and afoxolaner. Eprinomectin and praziquantel work together to kill worms and prevent reinfection. These ingredients are effective against the two most common species of tapeworms, two species of hookworms, one species of roundworm, and heartworms. Esafoxolaner, a form of afoxolaner, treats and controls fleas and ticks.

Best tablet for deworming and prevention

Interceptor is a great choice for pet owners who prefer to give an oral preventive rather than apply a topical product, thanks to the many parasites it protects against. In addition to preventing deadly heartworm disease, Interceptor Flavored Tablets treat and control roundworms and adult hookworms with the active ingredient milbemycin oxime. Each chewable tablet provides 30 days of protection and is safe for kittens as young as 6 weeks.

You can offer your cat an Interceptor tablet as a treat or hide it in a small amount of wet food. Interceptor is one of only two chewable parasite preventives available for cats, the other being Heartgard. Unlike Interceptor, Heartgard only treats and controls heartworms and hookworms, while Interceptor also treats roundworms.

To purchase NexGard Combo, you’ll need a prescription from your veterinarian. As with all heartworm preventives, your cat needs a heartworm test before starting this medication and once every year thereafter.

Our top cat dewormer picks compared

What to look for in cat dewormers

Before purchasing one of the best cat dewormers, it’s important to see your veterinarian. If you suspect your cat has worms, the first step is to take them to the vet for a physical exam and fecal test, which is an examination of the stool that reveals what type of worms your cat has. Depending on the type of worms found, your cat might also need follow-up deworming and another fecal exam to ensure all parasites have been eliminated

Your vet can also determine if your cat has other health issues that need to be addressed. 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. “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.”

Parasites prevented and other considerations: Even though some dewormers are available over the counter, do not skip the vet visit since different drugs treat different worms. Some drugs may also be more appropriate for your region and your cat’s specific health needs.

Safety and efficacy: The medication you give your cat should be approved by the Food and Drug Administration (FDA) or the Environmental Protection Agency (EPA). The FDA’s Center for Veterinary Medicine approves and regulates drugs for animals — you can search the Animal Drugs @ FDA database to see if a medication is considered safe and effective. Some flea and tick products for animals are instead regulated by the EPA since they contain pesticides. You can find out whether a flea and tick product is EPA-approved by searching the EPA’s Pesticide Product and Label System.

Ease of use and precautions: A medication may be oral or topical. Consider whether you can easily give your cat a pill by hand or mix it in their food. If you choose a topical medication, read the directions carefully to ensure you follow the appropriate precautions. You may need to wear gloves to apply certain medicines and keep other pets, children, or pregnant people away from treated animals for a specific period.

Be on the lookout for counterfeit products: Counterfeit parasite treatments can harm animals and may be unsafe for humans. For this reason, you should only purchase dewormers and parasite preventives from your veterinarian or a trustworthy pharmacy. The American Veterinary Medical Association (AVMA) provides advice for determining whether a pharmacy is trustworthy, which includes checking to see if an online pharmacy is accredited by the National Association of Boards of Pharmacy (NABP) Verified Websites Program. NABP-approved online retailers include Chewy, Petco, and Petsmart. The FDA also provides tips for verifying the legitimacy of a pharmacy, and the EPA says there are several ways you may be able to spot counterfeit products, including missing directions or directions that are not provided in English, foreign-labeled products, and a lack of child-resistant packaging.

Meet the expert behind this guide

Jackie Brown, freelance pets reporter: My knowledge about intestinal parasites, their treatment, and prevention is informed by my experience as a veterinary assistant and my 20-year career writing and editing for pet and veterinary publications. Prior to my career in publishing, I spent eight years working in veterinary hospitals where I assisted veterinarians as they treated dogs, cats, rabbits, pocket pets, reptiles, birds, and one memorable lion cub. During that time, I worked in nearly every area of the clinic, assisting with medical procedures and surgeries, administering medications and vaccines, conducting in-house lab tests, handling and restraining animals during treatment, grooming and nail trimming, and maintaining strict sanitation and safety protocols.

How we selected the best cat dewormers

For this guide to the best cat dewormers, I consulted two veterinarians for advice on treating and preventing intestinal parasites such as tapeworms, roundworms, and hookworms, as well as heartworms and ectoparasites such as fleas, ticks, and mites. Although this information guided my product selection, my 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.

Below are the main attributes I used to evaluate the best cat dewormers and preventives.

Safety and efficacy: I only considered FDA- or EPA-approved dewormers and preventives for this guide. I 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: With the exception of the tapeworm dewormer, the more parasites a preventive product covers, the higher I rated it.

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

Cat dewormer FAQs

What is the best cat dewormer?

The best deworming medication for your cat depends on several factors and should be determined by your veterinarian. “It’s important to see your veterinarian so they can identify what parasites are present and then prescribe the appropriate deworming medication,” Sawyer says. “Your vet can also explain any risks for human disease, which is also parasite-dependent.” Treatment options include single-dose deworming medications and monthly preventives that treat and control worms on an ongoing basis. Both types of treatments come in oral and topical forms.

Can I give my cat a natural dewormer?

Talk to your veterinarian before trying any natural deworming products. “When pet owners are looking for a product for their pet, I think they want research behind it,” Jeffer says. “Most of the time you really can’t guarantee that from a product that’s labeled ‘all natural,’ which hasn’t stood up to the research that FDA-approved products or EPA-approved products have gone through.” He adds that conventional, veterinarian-recommended dewormers are highly effective and very safe. “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 at the highest risk of intestinal parasites such as roundworms and hookworms, as well as heartworms, fleas, and ticks. However, indoor cats still need parasite prevention. Fleas can be brought inside the house by other pets or even on clothing, and indoor-only cats can still be exposed to other parasites. Jeffer says heartworms are the biggest concern 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 year-round, broad-spectrum parasite prevention for all cats. Some people assume protection is only necessary in spring and summer, but different parasites are active during different months, and parasite activity can vary depending on the region. Parasites can also become active earlier than expected, even in 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.

Cats that spend time outdoors are at higher risk of contracting intestinal parasites like roundworms, hookworms, and whipworms. However, all cats, including those that live only indoors, need protection against deadly heartworms. Sawyer says parasites can enter the home in several ways, including via other animals like the family dog or small rodents. Fleas can also be carried in on shoes or clothing, and mosquitoes that transmit heartworm disease can enter through open doors or windows.

What are the different types of worms in cats and their signs and symptoms?

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 says. “Kittens can actually die from parasite infestations.”

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

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.”

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.

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