When Should You Worm Your Cat or Dog?
Posted in: Companion Animals
Worming is one of those things that’s easy to put off – until you’re not sure when you last did it, or whether you even need to. The honest answer is that how often your pet needs worming depends on their age, lifestyle, and what’s happening in your household. There’s no single schedule that fits every cat or dog.
This guide walks you through exactly what’s recommended at each life stage, so you can keep your pet protected year-round.
Why Regular Worming Matters
Intestinal worms are more common than most pet owners realise. Dogs and cats can pick them up through contaminated soil, raw meat, uncooked bones, contact with other animals, and even from their mothers before or shortly after birth. Many infected pets show no obvious symptoms at all – which is precisely why a consistent treatment schedule matters more than waiting to see signs of a problem.
Some worm species can also affect people, particularly young children under five and anyone who is immunocompromised. Regular treatment protects your whole household, not just your pet.
Cat Worming: A Schedule by Life Stage
Kittens (2 weeks – 12 weeks old)
Kittens need worming every 2 weeks from 2 weeks of age through to 12 weeks. This frequent schedule reflects how vulnerable very young cats are and how quickly worm burdens can develop at this age.
Young Cats (3 months – 6 months)
Between 3 and 6 months, worming frequency drops to every 4 weeks.
Adult Cats (6 months and over)
For adult cats, the right schedule depends on whether your cat goes outside:
- Outdoor cats should be wormed every 3 months as a standard routine.
- Indoor-only cats can often be managed with testing or worming every 3 months, though your vet can advise based on your cat’s specific situation.
Always Worm More Frequently If:
Regardless of age, stick to a regular, frequent worming schedule if any of the following apply:
- There are young children under 5 in your household
- Anyone in your home is immunocompromised
- You have a pregnant queen
Dog Worming: A Schedule by Life Stage
Puppies (2 weeks – 12 weeks old)
Like kittens, puppies need worming every 2 weeks from 2 weeks old through to 12 weeks. Puppies are particularly susceptible to roundworm, which can be passed from mother to pup.
Adolescent Dogs (3 months – 6 months)
From 3 to 6 months of age, worming every 4 weeks is recommended.
Adult Dogs (6 months and over)
For adult dogs, how often you worm depends heavily on their lifestyle:
| Lifestyle | Recommended Frequency |
| Mixes frequently with other dogs (daycare, dog parks, multi-dog households) | Every 3 months |
| Mixes infrequently with other dogs | Every 6-12 months (or test regularly) |
| Eats commercial food only (kibble, roll, tinned) | Every 6-12 months |
| Eats raw meat or uncooked bones occasionally (monthly) | Every 3 months |
| Eats raw meat or uncooked bones more than once a week | Every 3 months – discuss with your vet |
Always Worm More Frequently If:
Some dogs should always be on a regular, frequent worming schedule regardless of lifestyle:
- Working dogs
- Households with young children under 5
- Households with immunocompromised family members
- Pregnant bitches
Not Sure What’s Right for Your Pet?
If your pet’s situation doesn’t fit neatly into one of the categories above – perhaps they have a mixed diet, spend time in multiple households, or you’ve recently adopted and aren’t sure of their history – the safest approach is to come in for a chat.
Our team can recommend the right product and schedule for your individual animal, and advise whether a faecal worm test is a better starting point than blanket treatment.
Frequently Asked Questions
How do I know if my cat or dog has worms?
Many pets with worms show no obvious signs at all. When symptoms do appear, they can include a pot-bellied appearance (especially in young animals), weight loss, scooting, visible segments in the fur around the tail, or changes in coat condition. Because worms are often invisible to the naked eye, sticking to a regular treatment schedule is more reliable than waiting for symptoms.
Can I use the same worming product for my cat and my dog?
No – cat and dog wormers are different products and should never be interchanged. Some ingredients safe for dogs are toxic to cats. Always use a product specifically labelled for your pet’s species, and check with your vet if you’re unsure.
My pet is indoor-only. Do they still need worming?
Indoor cats and dogs have a lower risk, but it’s not zero. Worm eggs can be brought in on shoes, and fleas (which can carry tapeworm) can still find their way inside. A reduced schedule may be appropriate, but we’d recommend discussing this with your vet rather than skipping treatment entirely.
What’s the difference between worming treatment and a worm test?
A worm test (faecal egg count) checks a stool sample for worm eggs to confirm whether your pet actually has worms before treating. This approach can be useful for lower-risk adult pets on an infrequent schedule. For higher-risk animals – young pets, those on raw diets, or those with children in the household – routine treatment on a set schedule is usually more practical.
Are there worms in New Zealand I should be particularly aware of?
Yes. The most common intestinal worms in New Zealand dogs and cats include roundworms, hookworms, whipworms (dogs), and tapeworms. Lungworm is also present in some regions. Your vet can advise on which parasites are most relevant in the South Canterbury area and whether your chosen product covers all of them.