Deworming a cat involves giving an oral antiparasitic medication that kills intestinal worms including roundworms, tapeworms, hookworms, and whipworms. Kittens should be dewormed starting at 3 weeks of age, every 2 weeks until 8 weeks, then monthly until 6 months. Adult cats should be dewormed every 3 months if they go outdoors or hunt, or every 6 months if they are strictly indoor cats.

Intestinal worms are one of the most common health problems in cats worldwide — and one of the most commonly missed by pet owners, because many cats show no obvious symptoms until the infestation is significant. Whether you have a new kitten, a rescue cat, or an adult outdoor cat, understanding how deworming works, how often it needs to happen, and which signs to watch for will help you keep your cat healthy year-round. This guide covers everything a cat owner needs to know, explained in plain language by a vet.

Which Worms Affect Cats?

Several types of intestinal parasites can infect cats. Each requires slightly different treatment, which is why broad-spectrum dewormers are preferred:

Signs Your Cat Has Worms

Many cats — especially adult cats with low worm burdens — show no symptoms at all. This is why routine deworming on a schedule is more reliable than waiting for visible signs. When symptoms do appear, they include:

• Visible worms or worm segments in faeces or around the anus — tapeworm segments look like small grains of rice
• Pot-bellied appearance — particularly noticeable in kittens with heavy roundworm loads
• Weight loss despite a good appetite — worms compete for nutrients
• Vomiting — sometimes with visible worms in the vomit in heavy infections
• Diarrhoea — may contain blood or mucus in hookworm infections
• Dull, dry coat — chronic worm infestations affect coat condition
• Scooting on the floor — caused by tapeworm segment irritation around the anus
• Lethargy and poor growth — especially in kittens

Important: A negative faecal test does not always mean your cat is worm-free. Worm eggs are shed intermittently, so routine deworming by schedule remains the most reliable approach.

The Vet-Recommended Cat Deworming Schedule

How to Give a Cat Deworming Medication

Most dewormers for cats come as tablets. Cats are notoriously difficult to tablet — here are the most reliable methods:

• Hide in food: Crush or break the tablet and mix with a small amount of strong-smelling wet food. Check the product — some dewormers can be given with food, others must be given on an empty stomach.
• Pill pocket: Wrap the tablet in a small ball of wet food or a purpose-made pill pocket treat
• Direct administration: Hold the cat’s head, tilt back gently, open the jaw, place the tablet at the back of the tongue, close the mouth, and stroke the throat to encourage swallowing. A syringe of water helps wash it down.
• Paste or liquid formulation: Some dewormers are available as pastes or oral liquids — easier to administer to resistant cats

Always check whether the dewormer needs to be given with or without food, and follow the weight-based dosing on the label precisely.

Can Worms Spread from Cats to Humans?

Yes — some cat worms are zoonotic, meaning they can infect humans. This makes deworming not just a pet health issue but a family health issue.

• Toxocara cati (roundworm): Eggs shed in cat faeces can survive in soil for years. If accidentally ingested — especially by young children playing in soil — they can cause visceral larva migrans, a condition where worm larvae migrate through human tissue. Regular hand-washing and deworming your cat significantly reduces this risk.
• Dipylidium caninum (tapeworm): Spread through ingesting infected fleas. Rare in adults but can occur in young children. Year-round flea prevention on your cat is the key preventive measure.
• Hookworms: Larvae can penetrate human skin from contaminated soil, causing cutaneous larva migrans — an itchy, red tracking rash. More common in regions with warm, moist climates.

Does My Indoor Cat Really Need Deworming?

Yes — though less frequently than outdoor cats. Even strictly indoor cats face worm exposure through:

• Contaminated food brought in from outside (rodents, insects)
• Fleas carried in on human clothing or other pets
• New rescue cats introduced to the household
• Occasionally, through raw food diets containing undercooked meat

A deworming schedule of every 6 months is recommended for indoor-only cats. This is a small investment to protect both your cat and your household.

Frequently Asked Questions — Deworming Cats

Q: How often should I deworm my cat?

A: Kittens should be dewormed every 2 weeks from 3 to 8 weeks of age, then monthly until 6 months. Adult outdoor or hunting cats should be dewormed every 3 months. Indoor adult cats can be dewormed every 6 months. Cats with unknown history should be dewormed immediately and repeated 2 weeks later.

Q: What are the signs that a cat needs deworming?

A: Common signs include visible worm segments around the anus (tapeworms look like rice grains), pot-bellied appearance in kittens, vomiting, diarrhoea, unexplained weight loss, dull coat, scooting on the floor, and lethargy. However, many cats show no signs at all — routine scheduled deworming is more reliable than waiting for symptoms.

Q: Can I buy cat dewormer without a vet prescription?

A: Some over-the-counter dewormers are available, but they often cover only one or two worm types. Prescription-strength broad-spectrum dewormers covering roundworms, tapeworms, and hookworms in one dose are more effective. If you’re unsure which worms your cat has, a vet faecal exam or a broad-spectrum product is the safest approach.

Q: How long after deworming do worms come out?

A: Dead worms and worm fragments typically pass in the faeces within 24–48 hours of deworming. You may see worms in the litter tray in the days following treatment — this is expected and confirms the medication is working. Some products kill worms before they are shed, so no visible worms doesn’t mean the treatment failed.

Q: Is it safe to deworm a pregnant cat?

A: Some dewormers are safe during pregnancy and some are not. Fenbendazole is generally considered safe for pregnant queens. Praziquantel and pyrantel combinations should be used cautiously. Always inform your vet that your cat is pregnant or nursing before any deworming treatment to ensure the product used is appropriate.

Q: Can I deworm a kitten at home?

A: Yes, with the correct product and dose. Use a kitten-specific dewormer dosed by weight. Start at 3 weeks of age and repeat every 2 weeks until 8 weeks. Do not use adult cat products on kittens without vet guidance — the dosing differs significantly. If the kitten is very young or unwell, a vet visit is strongly recommended.

Q: Do I need to treat all cats in the house at the same time?

A: Yes. If one cat in a multi-cat household has worms, all cats should be treated simultaneously to prevent reinfestation cycling between animals. This is especially important for tapeworms spread through shared flea exposure.