Cat Deworming: What to expect after Deworming a Cat?

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Updated on: 01/24/2023

According to veterinarians, worms in cats are so common that any of our pets in their lives at least once suffered from this disease. Many types of worms in animals are dangerous for humans, especially children. Most pet owners are convinced that in the summer, their cats and dogs are most often infected with worms, and therefore it is enough to treat them with an anti-worm drug in the spring and autumn and forget about this event until the subsequent warming. In fact, this is not the case. Preventive measures of such drugs in the spring and autumn are essential, but they should be used in other situations.

cat deworming and what to expect after deworming a catImage by @begonvilliev from Pixabay

Even if the cat does not leave the apartment, endoparasites may be present in its body. Helminth eggs enter the room on the owner’s shoes or clothing and various items that contact the soil. If the pet has free access to the street, one or more parasites are necessarily present in its body.

Timely deworming allows you to quickly free the cat’s body from parasites and prevent infection of other family members or pets. Veterinarians recommend regular medical and preventive measures.

How can a Cat get Worms?

Helminth infection occurs regardless of the temperature regime and season, although the frequency increases in summer. This should be taken into account when choosing a cat deworming scheme.

There are several ways how your cat can be infected with worms:

  • getting parasite eggs into the house on the owner’s shoes;
  • eating meat or fish that has not passed vet control and has not been subjected to heat treatment;
  • eating contaminated food (for example, contaminated feed);
  • accidental ingestion of a flea carrier of the larval form of helminth;
  • eating an infected hunting object (rats and mice);
  • infection of offspring from the mother.

READ MORE: What is the Best Shampoo for My Cat?

Infestation Symptoms in Cats

Regardless of what type of worms an infected pet has, the symptoms are similar. Helminthiasis is manifested by such changes in the state of animal health:

  • loss of appetite;
  • the dullness of the coat;
  • dramatic reduction in total weight over a short period;
  • unproductive, frequent cough;
  • intestinal obstruction, constipation, or Vice versa;
  • lethargy.

When the worm infestation is severe, in the feces, under the tail, on things, you can see helminths or their eggs, and sometimes the animal vomits. The type of worms can only be determined in the laboratory. Based on the test results, the veterinarian will select an anthelmintic that will help get rid of the infection quickly. After a course of anthelmintic therapy, you need to take sorbents. They are required to save the body of a sick cat from intoxication by dead nematodes.

how cat can get wormsPhoto by Clark Young on Unsplash

READ MORE: Cat Toxoplasmosis

Each of the symptoms requires medical attention. Visit a veterinarian and perform treatment according to the prescribed scheme. You can choose the wrong type of medicine and give it in an insufficient dosage, leading to relapse, deterioration of the animal’s condition, and repeated therapy.

Helminths can be asymptomatic in the body of a dog or cat for a long time. And they are already at a late stage of infection when the animal begins to refuse to eat, lose weight, vomit, or have diarrhea. Animals are dewormed several times a year. The harm is minimal from medications taken for preventive purposes compared to serious worm infestations that can infect the pet and all family members, including small children.

The process of Cat’s Deworming

The process of deworming is necessary because many types of worm infestations are transmitted to humans. Especially if there is a small child at home, it is essential to do prevention regularly.

If your pet has already developed the disease symptoms, do not self-medicate and contact a veterinary clinic. Helminths can affect the liver, heart, lungs, and intestines, and with inadequate treatment, cause irreparable damage to the animal’s health. When given the drug, pay attention to the dosage. If you do not follow the doctor’s recommendations or precautions specified in the drug’s instructions, the animal may die or be poisoned.

To rid the cat of worms, you need to give it an anthelmintic drug. Veterinarians recommend the use of medications for the broad scope of the killing round and tapeworms.

Veterinary medicines for worms are produced in the form of tablets, but there are anthelmintic drugs in the form of drops that get rid of worms and ectoparasites. They are applied to the withers and distributed over the entire ridge.

The first deworming of kittens is carried out at the age of three weeks using drugs in a small dosage. There are special preparations for kittens. Then, every two weeks, the procedure is repeated until the first vaccination. Anthelmintic drugs mustn’t be used during the vaccination, and after it is completed, the pet is dewormed every three months. Each such event is recorded in the animal’s veterinary passport (drug name, date, and dosage).

Cats should be dewormed two weeks before the ligament, before vaccination, and 21 days after lambing. At this time, the offspring are also driven away by worms. You need to give drugs in the morning to be able to monitor the condition of the cat. If the pet has fleas, they also need to be treated to avoid relapse.

The criteria of the proper cat deworming:

  • The choice of the drug according to the spectrum of action. The agents may be active against nematodes, cestodes (larvae and/or adult worms), and ectoparasites. Now, most of the drugs are universal.
  • Correct selection of the dosage form of an anthelmintic drug. A calm animal can be rid of worms using tablets or suspensions. For aggressive cats, it is convenient to apply drops on the withers.
  • Calculation of the drug dose based on the weight of the pet. Compliance with the plan of deworming, if necessary, the alternation of different drugs.
  • Taking into account the individual characteristics of the pet. If a cat is hypersensitive to one of the drug’s active components, it is essential to contact a specialist for help and immediately select another drug.
  • To minimize the risk of infection with parasites, you should regularly clean the tray with a complete replacement of the filler, rinse with boiling water and disinfect the tray itself, do not give the cat raw fish and meat if there is suspicion of their safety, and do not allow contact with stray animals.

After antiparasitic drugs, worms in cats and dogs come out with feces for the first few days. To completely stop the parasite’s development cycle, it is necessary to carry out treatment two times with an interval of 10 days.

READ MORE: When to feed kittens?

how to prevent cat from getting wormsImage by @platelicker from Pixabay

How to prevent Cat from getting Worms

Both domestic and street cats need regular deworming. Due to the body’s low weight and characteristics, a neglected helminth infestation in cats is not always cured, even with shocking doses of modern drugs. Do not wait for symptoms of an infection; planned prevention will provide your pet with reliable protection.

Preventive procedures are carried out every three months for animals that go outside or eat fresh fish, poultry, minced meat. Domestic cats that eat dry food are given medications twice a year.

Carrying out preventive deworming is much more useful than fighting existing parasites inside the animal. In addition to the presence of parasites in the animal’s body, there is a risk of various diseases against this background. The latter leads to a decrease in the immunity of a cat or dog. Secondly, it is natural that it is much easier to solve the issue of purchasing antihistamines financially than with an additional huge list of medications for the consequences of infection with worms.

You need to follow simple rules that will help prevent infection of your pet. Worms in cats will not appear if you follow the following measures:

  • Avoid contact with infected animals.
  • Regularly treat animals with special remedies for ectoparasites, even if your pet is not on the street and does not communicate with fellow animals.
  • Feed with high-quality feed. Give the animal only fresh food and always put it in the refrigerator or throw away the remains of food that has been lain in the cat’s bowl for a long time. Completely exclude raw river fish from the diet.
  • Keep your shoes in closed lockers, especially if you have a pregnant cat or small kittens at home.
  • Medicines for the prevention of worms in cats are given two weeks before mating and vaccination.
  • To monitor the cleanliness of the cat tray and cat bowls. To avoid infection, it is recommended to clean the cat’s toilet in disposable gloves and follow basic hygiene rules.

Unfortunately, it is not always possible to fully adhere to the rules described above, but you can reduce infection likelihood. Prevention of worms in cats can also consist of folk remedies, but their effectiveness is questionable.

Side effects of Worm medications

Different types of worms are affected by various drugs, respectively, for the treatment of helminthiasis of different types may require different drugs. Currently, you can buy both products based on a single active substance and broad-spectrum drugs.

Most often, anthelmintic drugs are based on praziquantel and pyrantel. The mechanism of their action is a violation of the permeability of cell membranes and changes in the energy processes of the parasite’s body, which leads to its paralysis and death. The drug, along with the destroyed helminths, is excreted with feces from the cat’s body. The mechanism of action of other drugs is similar. They act directly on the parasite, not on the cat itself (these substances are low-toxic for warm-blooded animals).

However, sometimes it also happens that a particular active substance does not cope with the destruction of all helminths that parasitize the cat’s body. There are either too many of them, or they have managed to adapt to the action of the drug used. Besides, the drugs only affect adult parasites, without destroying their larvae. If the animal is severely affected by worms or notices parasites in the feces, it is recommended to re-give the cat the medication. The interval between the administration of anthelmintic agents is 10 to 14 days. Many veterinarians also advise you to change the active substance every time you carry out helminthiasis prevention.

Anthelmintic drugs can control the same group’s parasites, for example, only tapeworms or only roundworms. However, the most common broad-spectrum medicines that help fight simultaneously with different types of worms, and sometimes even with the simplest organisms that can also affect the cat’s intestines and cause serious diseases. In veterinary pharmacies, you can find anthelmintic drugs of various firms and forms. If you do not have a special doctor’s appointment, then you can choose the tool that will be easiest for you to apply.

Some medications may have side effects; for example, cats often have a stool disorder or diarrhea when using sugar cubes. Drops on the withers are not recommended for use in the presence of unhealed wounds and skin damage.

Before you feed the cat an anthelmintic drug, you need to read the instructions. Anthelmintic drugs are usually given to the animal once in a strictly defined dose. It is not recommended exceeding the dosage, although many manufacturers promise that there will be no side effects. Still, it would be best if you didn’t experiment on your cat. Unfortunately, cases of poisoning with well-known remedies for worms are not uncommon.

The dosage of the drug is calculated based on the weight of the cat. Therefore, every time before using the medicine, the cat must be weighed — it could significantly improve or lose weight. Sometimes tablets need to be crushed, dissolved in water, and calculate the resulting suspension dosage. Besides, not all drugs can be combined with different medications or with each other when using single-component drugs. Not all anthelmintic drugs are suitable for pregnant and nursing cats and kittens under 3 months of age, which is better to buy a unique product marked “for kittens”.

side effects of worm medications in catsPhoto by Andrew Kondrakov on Unsplash

There are several contraindications for deworming:

  • The animal is weakened as a result of recent surgery or a serious illness.
  • The cat has a severe infection that is not associated with the presence of endoparasites in its body.
  • The animal is too exhausted.
  • The pet is diagnosed with serious pathologies of the liver and urinary system. This is directly related to the elimination of active substances of Anthelmintics.
  • Pregnancy and lactation. In this case, deworming is performed only after prior consultation with a veterinarian (a drug with minimal toxicity may be prescribed).
  • Powerful infection with helminths. Deworming is mandatory but under the supervision of a doctor. In such cases, an individual treatment regimen for helminthiasis is prescribed.

FAQ

How long after deworming a cat are the worms gone?

Usually, after you give your cat a dewormer, the worms will be gone in 2 to 3 days. Sometimes it may take a second deworming a few weeks later for all the worms to be gone. Cats are known for keeping themselves clean. This means that they can reinfect themselves with parasites. 

Your cat may lick their rectum when they have parasites eggs in that area. This causes them to reinfect themselves and possibly need another dewormer. 

Do cats feel ill after deworming?

Most cats do not feel sick after they receive a dewormer. Usually, dewormers cause your cat to feel much better.

What are the side effects of worms in cats?

If your cat has worms, there are many signs that you may see. Common signs of parasites in cats are diarrhea, vomiting, bloated abdomen, and coughing.

Can I deworm my cat myself?

Yes, you can easily deworm your cat yourself. While you may need to get the medication from your vet as many of them, over-the-counter dewormers do not treat all parasites that your cat may have. You should be able to administer this to your cat efficiently. It will either be a liquid or a tablet that you will give to your cat by mouth. Some dewormers are even a topical application like many of the flea and tick medications for cats are. Also, it makes it even easier to give to your cat.

ThePets is an informational website that features articles written by qualified veterinarians and professional writers. You can learn more about our editorial process. When selecting food for your pet, use Pet Food Finder, and search for the clinic to treat your pet using Vet Clinics Locator.

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19 comments

Rolandon May 05, 2021

I can’t say that I have ever dealt with cat dewormers before so I had no idea where to start. If you want to know about medication, dewormers, fleas, tapeworms and more, I recommend that you read this article. At least now I know how to tell if the dewormer is working!

Reply

Sharonon June 21, 2021

Thank you for this article! We have two adult cats, and both struggled with roundworms in the past. Our veterinarian had never seen such severe issues before. He gave us a prescription for oral dewormer. We used it to remove the worms, and it took around 3 days and plenty of weight loss for our babies. Now they’re fine, but we keep the treatment handy just in case.

Reply

Sol ajetoon July 16, 2021

July 15 i gave 1 ml of deworming to 3 week old kitten (250grams) but only 3 worms came out and very few poops came out, then july 16 i added .5ml again of dewormer to the kitten.is that ok? Because i feel the dosage is not enough?

Reply
    Anastasia Bilohub

    Anastasia Bilohubon July 19, 2021

    Dear Sol Ajeto, as mentioned in the article, many things affect how deworming medication works. Please be sure that you’ve checked:
    – instructions and gave the dose correct for your cat age/weight;
    – there needed time passed for effect.
    If you think that the drug didn’t work, it might be because not all drugs are universal, and you dewormed your cat for a specific type of worms.

    In any case of side effects or doubts, please contact your local veterinarian for consultation.

    Reply

Terri Stegallon October 03, 2021

How long should a kitten have diarrhea after deworming

Reply
    Anastasia Bilohub

    Anastasia Bilohubon October 04, 2021

    It should take about 24 hours for any side effects to dissolve. If it’s been more than 24 hours passed and your kitty still has diarrhea, it is better to consult a veterinarian.

    Reply

Vimaon April 17, 2022

Can you touch cat after deworming

Reply
    Anastasia Bilohub

    Anastasia Bilohubon April 19, 2022

    Mostly it depends on the specific cat and their situation. If it’s a preventative measure for each 3-month cycle or before vaccination or mating season, then do not worry! You can safely pet your cat.

    In other cases, if your cat showing symptoms of having worms, then be careful and follow all steps mentioned in the article, and do not hesitate to consult your vet before and during deworming treatment.

    Reply

Kris Ditanon June 12, 2022

Hi! This article was very helpful. My 9-month old cat vomitted worms a few days ago. We consulted a vet this morning and she was given a deworming tablet with some prescribed antibiotics and vitamins . She has not eaten nor taken any fluids since last night and it worries me as she still is very lethargic. She hasn’t urinated nor pooped yet for the whole day. The vet told me the parasitic infection might have gone to a serious stage. Are her symptoms normal even after deworming? Thank you in advance.

Reply
    Dr. Linda Simon

    Dr. Linda Simonon June 13, 2022

    I’m sorry to hear your cat is poorly.

    No, these symptoms aren’t expected from either worms or a wormer and we’d be concerned there’s more going on such as a secondary infection or gut blockage.

    As she’s not eating and hasn’t passed urine, I’m concerned she may be in shock and she might also be dehydrated.

    I’d want her seen for a re-check right away.

    They’ll examine her and she may need to be admitted for a drip and further medicine. If concerned for a blockage, the vet may advise on some abdominal imaging to check for one.

    Hopefully, she’s back to herself very soon.

    Reply

Maxwell Hunteron June 20, 2022

We just adopted a kitten about 4 weeks ago. She is now 2 months old as her birth was probably in late April. Well, my mom and her grand daughter noticed the kitten scooting. She spoke to me and I told her that there is a possibility that she has worms and that she needs to find a vet to build a relationship with regarding vaccinations and future care. So they gave her an antibiotic. 5 syringes and 1 pill. So far she has taken 4 of the 5 syringes and the pill. She has one syringe left. My mom will have to provide a stool sample once the medicine is completed. Then she’ll have to come back in a week. And next month for her other shots. My mom is worried because the kitten has been listless. She eats, drinks, plays, but she sleeps a lot. My mom is worried that she’s more sick. But I figured that we need to give the medicine some time to work and maybe her body is fighting to push everything out. But she’s been laying around a lot. I did read on here about swelling in the stomach and my mom said that she does look like she lost weight. So we’re not sure if the weight loss is due to the medicine working or something else. I advised her that if she is worried, she can always call the vet and let them know her concerns. And this way if they want to see her sooner they can administer more care if needed. This is my first time seeing the new kitten so she’s already becoming part of the family as she is a offspring of a stray mother. Which is why now my mother contacted the family that is holding the mother and the other kittens to get them also checked out. But I’m worried. But maybe it might be nothing. I just hope it’s just the process of healing and that it’s not something else.

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Allen Bongalontaon July 06, 2022

Is it normal for my kitten to eat a lot after deworming? she’s 3 months old*

Reply
    Dr. Linda Simon

    Dr. Linda Simonon July 11, 2022

    Deworming itself should not cause an increase in appetite, no. However, at 3 months old a kitten will be growing a lot and a growth spurt can mean an increased appetite. If they are only eating more that same day, it may be that worming them has stressed them out (for example if a tablet was giving into their mouth) and the higher stress levels has spiked their appetite temporarily.

    Reply

Maryanon July 19, 2022

Thank you so much for this detailed and well explained article, except there’s one question, we had bad experience with vets around our area and we are in desperate need for advice.
We adopted a kitten(male), who’s below the age of 4 months (he’s about 2.5-3 months old), first couple of days the kitten was active and playful, whenever he pooped there was a red lining outside of his anus (as his anal glands were swollen) and after he was done it went back to normal as if nothing happened. But a week later his level of activity gradually decreased, eventually he stopped playing or reacting, he ate still and used to litter (with the same issue), I didn’t see any worms in his stool back then, his eyes became watery and a little red; we called a vet, they said it was 100% worms. We gave the kitten a dose of vitaminthe virbac paste and kept hydrating him with electrolyte water (alfalyte), he vomited 2hours after the dewormer. A day later there was diarrhea with blood and mucus, the vet prescribed to use antibiotics, so we did. Yesterday the cat was normal, diarrhea stopped, he ate well (in case needed, we feed him royal canin dry food), was hydrated, and was much more active regardless of antibiotic side effects.
Today however, his stool was normal, yet he went to litter frequently (4times, 3 times in morning and once afternoon), is this normal? Is this a sign of progress and healing? How must healing stage look like after deworming?

Reply
    Dr. Linda Simon

    Dr. Linda Simonon July 20, 2022

    Thanks for this question!

    After worming, we may see some worms in the stool (but not always) and it is not uncommon for there to be a short spell of diarrhoea. Stool should soon return to normal, over the course of a couple of days. Kittens often pass regular stools at this age and we’d normally expect 2-3 stools per day. So this amount would not be abnormal.

    Reply

      Maryanon July 20, 2022

      Thank you so much for the reply!!
      I forgot to mention the kitten has blood in his stool as well, it’s like fresh drop of blood after he is done, what could it possibly be? And how long will this last?

      Reply

Katon August 02, 2022

I think your cat might eat a lot after worming when compared to their loss of appetite when the worms were flourishing. My cat got his appetite back with a vengeance after worming him, but he hadn’t eaten as much as normal before the worming. I figured his appetite was a sign that the praziquantel was shrinking the worms in his gut so he didn’t feel so full? Hope all your babies heal quickly.

Reply

Gabriellon August 27, 2022

Hello, I’m here to speak about snowball he’s about 10 weeks of age we have him hes weekly dawn bath an picked all the fleas off he had a ton counted about 25, we noticed for the next 3 days all he’s been doing is sleeping we thought nothing of it cause he would come lay with me then the 4th I directed to call the vet they couldn’t get me in till next week yet they agreed to give flea medication an a de womer to be safe he got better an ran around an played then now to this day we woke up an couldn’t find him till we looked in our 2 adult cats litter box he was asleep he never goes in that room he usually stays in the living room or kitchen he has his own litter box set up in the living room he’s never been showed the adult ones but we found him called the vet trying to get a quicker appointment we didn’t think he would make it threw the weekend (his appointment is Monday) ( it’s friday now gave him the meds yesterday) he’s worse ! He’s so weak he can even lift his head not eating or drinking just lays there heavy breathing an paralyzed hasn’t used the bathroom at all. So the vet said to give him kitten milk mixed with kitten chow high protein (we thought he was anemic we didn’t know what was wrong didn’t think he had worms) I syringe feed him 2 of them every hour from about 4 ish till now almost 1 am no bowel movement he fartwd 3 times an I noticed a worm on his butt it was small but alive then it died moments later idk what to do he’s still laying on me just struggling to breath he tries to get up but just falls back over an now he’s made 3 small noices of pain I think .. please help. Let me know if I can do anything else for him at least please…

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Sarahon October 07, 2022

I have my 4 month old kitten half a tablet of dewormer and she threw up once but i noticed she’s urinating a lot but i don’t think she’s peeing every time she’s going. What’s wrong?

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