Treating Worms in Dogs and Cats

Parasites, such as roundworms, hookworms, tapeworms, whipworms, and fleas, can infest dogs and cats and make them sick. Some types of worms, such as heartworms, can even be fatal to dogs and cats. To protect your dog or cat from intestinal parasites, you need to understand how they are transmitted, what symptoms to look for, and what to do to prevent an infestation.

Worms take up residence in a dog or cat's intestines, feeding off their blood and causing various symptoms that can make them feel ill.

• ‌Roundworms:‌ Adult roundworms are long, spaghettilike parasites that can grow to be 3 to 7 inches in length, making them easy to see. They infect both dogs and cats and can also be spread to humans through a pet's kisses (saliva).
• ‌Hookworms:‌ At only about 1/8 of an inch long, hookworms are difficult to see with the naked eye and are often not discovered without a veterinarian exam. However, they are able to consume a large amount of blood once they attach themselves to the wall of the dog or cat's intestinal tract with their hooklike mouthpart, often causing severe anemia.
• ‌Tapeworms:‌ The segments of tapeworms appear in a dog's poop but they are difficult to see, as they look like grains of rice. Tapeworm segments may appear like tiny, moving inchworms when an infected dog or cat is pooping, but once they dry up, they look more like small white sesame seeds. These segments contain the tapeworm eggs.
• ‌Whipworms:‌ If your pet's poop has what appears to be tiny pieces of thread that are enlarged on one side, it could be whipworms. Whipworm eggs are microscopic, which means they are not visible to the human eye.

There are several ways parasites can be transmitted to dogs and cats. Puppies and kittens may pick up worms from their mother in the womb or through their mother's milk while nursing. It is not uncommon for puppies and kittens to have worms, which is why veterinarians routinely deworm kittens from a young age and check for worms as part of "puppy exams," providing deworming medications as needed.

Adult dogs can also pick up worms by eating dog poop from another dog that has them; by the ingestion of grass that has been contaminated by an animal with worms; or through the hunting and eating of infected birds, rabbits, insects, etc. Fleas are common transmitters of tapeworms, so when dogs or cats have fleas, licking or grooming themselves can cause them to ingest fleas containing tapeworm larvae. Dogs and cats get heartworm through the bite of an infected mosquito.

‌Yes, even indoor cats can get worms.‌ While dogs generally spend time outdoors, many cats do not. This does not preclude indoor cats from getting worms, however. Mice, flies, insects, and other household pests can carry worm eggs, and if a cat eats them, they can become infected.

Outdoor cats are at greater risk for worms than indoor cats. Feral cats with roundworms can pass microscopic eggs in their feces. If your cat sniffs or licks that contaminated soil, they can end up with a roundworm infection. Hookworms can penetrate a cat's skin just by walking by or lying down in an area that is contaminated.

Cats are less likely to get heartworm than dogs since worms do not thrive as well in a cat's body. However, this does not make them immune to heartworm. If an infected mosquito bites a cat, it can transmit heartworm larvae to the cat.

In some cases, you can actually see worms in a dog's stool, but not all worms are visible. Some of the other symptoms of worms in dogs include:

• Diarrhea
• Scooting
• Unexplained weight loss
• Abdominal pain
• Vomiting
• Dull coat
• A pot-bellied appearance
• Lethargy
• Dehydration
• Anemia
• Intestinal blockage
• Blood in the stool

In cats, many times the first sign of worms is seeing a visible presence of worms or parts of worms in the litter box. Other common symptoms of worms in cats include:

• A dull or poor-quality coat
• Pale gums that appear white or gray rather than a normal, healthy pink
• Vomiting
• A change in bowel movements, such as dark, tarry stool or diarrhea
• Unexpected weight loss
• Increased appetite

Panacur, or fenbendazole, is an over-the-counter medicine that treats roundworms, whipworms, hookworms, and one type of tapeworm. However, Panacur doesn't treat all parasites, so a visit to the veterinarian may still be necessary. Panacur is also not recommended for puppies under 6 weeks of age, so for puppies with worms, a prescription dewormer will be needed. Panacur is not FDA approved for cats; however, veterinarians sometimes prescribe it for common intestinal parasites, such as roundworms, hookworms, whipworms, and Giardia. It is generally considered safe for adult cats and kittens over 2 weeks of age.

Praziquantel is a medication used to treat many different types of parasitic worm infections. Originally created for humans, its use in dogs and cats is considered off label, so it's important to follow your veterinarian's dosing instructions carefully. It's usually given in oral form, not injectable form. But if your dog does get an injection, side effects in dogs include pain at the injection site, diarrhea, vomiting, drooling, tiredness, decreased appetite, and staggering while walking. Side effects in cats are considered rare but may include drooling or diarrhea.

The treatment for heartworm disease in dogs will depend on several factors, including how long the dog has been infected. If the disease has advanced too far, the dog may not be able to survive treatment. In these cases, the veterinarian may opt to just treat the symptoms. However, in most cases, heartworm disease can be treated with Melarsomine, which is an injectable drug that kills adult heartworms. It is administered in a series of injections, often in conjunction with the antibiotic doxycycline. While Melarsomine is more effective than treatments of years ago, it still means a challenging recovery that requires months of rest. Some dogs will still suffer from heart failure that requires lifetime care.

There is currently no approved drug for treating heartworm disease in cats. The drug approved for use in dogs has many side effects in cats and can be life-threatening, so veterinarians are often left with the option of treating the symptoms and hoping the cat outlives the worms or, in the most severe cases, surgically removing the worms, which poses significant risks. This is why prevention is so important.

The best way pet owners can prevent worms in dogs and cats is to keep them on year-round medication that protects against worms. Many heartworm preventatives also protect against hookworms and roundworms, while flea preventatives can also protect against tapeworms.

Taking your dog to the veterinarian for an annual fecal test will also help to catch any problems early. By providing a simple stool sample, the veterinarian can make sure that the dog's feces is parasite-free.

Dog owners should also be wary of places such as dog parks, where many dogs congregate and contaminated feces can create a greater risk of picking up intestinal worms. Communal water bowls can also pose a risk if the water is contaminated, so if your dog frequents the dog park, be sure to bring your own water and water bowl and don't let your dog share water with unknown dogs. Additionally, never allow a dog to eat feces or lick an area where other dogs have relieved themselves.

Keeping cats indoors contributes to their overall wellness and safety and helps to minimize the risk of parasites. In general, cat health is enhanced by indoor living, but in cases where this is not possible, high-quality cat food, regular veterinary checkups, and regular vaccinations and flea treatments are essential.

While home remedies such as carrots; chewing tobacco; garlic; and natural herbs, such as peppermint and cinnamon, are often suggested as natural alternatives for treating worms, these are not recommended. In some cases, they may even be dangerous. Garlic and tobacco are listed as toxins by the ASPCA.

Parasites, such as roundworms, hookworms, tapeworms, whipworms, and heartworms, can be harmful or in some cases even fatal to cats and dogs. Depending on the parasite, they can be transmitted via insect bites, sniffing or eating an infected animal's poop, or even sniffing or lying in an area where an infected animal has been. Year-round preventative medications — which can be a topical liquid or chewable oral medication — can protect dogs and cats from many parasites, while regular veterinary visits can help to identify problems before they become more difficult to treat.