My kitten lives strictly indoors: does it still need deworming?

Yes. Even a kitten that will never go out can be born already infected, because roundworms pass from the mother. Eggs also come in on shoes, and fleas, which carry tapeworms, reach flats too. The plan in the first months is much like that of a puppy destined for the outdoors; later, the adult frequency will be lower but rarely zero. You settle it with the vet based on lifestyle.

I saw worms in the stool after treatment: did I do something wrong?

No, it is normal and in fact a sign the product worked. The wormer paralyses or kills the parasites, which are then passed in the stool over the following hours or days. What matters is repeating the treatment on schedule, because a single dose does not cover the eggs that will hatch afterwards. If you keep seeing worms weeks after each dose, though, mention it to the vet.

Can I use a wormer bought for an adult dog on the puppy?

Not without checking. Many adult products are not licensed below a certain weight or age, and an adult dose can be wrong for a small animal. Use a formulation indicated for the age, dosed on the puppy's real weight. If the only product at home is for adults, ask the vet before giving it rather than estimating the dose yourself.

Can deworming and the first vaccine happen on the same day?

Often yes, and it is common to arrive for the vaccine already dewormed. Many vets prefer the young animal to have been wormed a few days before the vaccine, because a gut loaded with parasites responds less well. Agree the sequence when you book, so you reach the clinic with the plan already clear.

The first months20 minLevel: BeginnerUpdated on August 20, 2026

Scheduling puppy and kitten deworming in the first months

Intestinal worms in the early weeks: why treatment starts at two weeks of age, how often to repeat it and how to log each dose so none gets missed.

Audience: Pet owners, Breeders
Species: Dog, Cat
Scope: Valid everywhere, Italy, European Union

What you need before you start

Il peso attuale del cucciolo o del gattino, perché quasi tutti i vermifughi si dosano sui chili
La data di nascita o una stima ragionevole, per sapere a che punto del calendario ti trovi
Il nome del prodotto già usato dall'allevatore o dal rifugio, se il piccolo ne ha già ricevuto uno

A puppy or kitten is almost always born carrying a few intestinal parasites, and not because anyone did anything wrong: many worms pass from the mother during pregnancy or through her milk, before the young one even opens its eyes. That is why deworming does not wait for vaccines, it starts much earlier, and in the first months it follows a tight rhythm that only later slows down. This guide explains why the calendar starts so early, which worms actually affect the young, how often to repeat treatment, and how to keep track of doses without missing one during the window when they matter most. It does not replace your vet, but it gets you to the first visit with a clear plan instead of one more question.

Why the calendar starts before the vaccines

Many people assume a young animal's health begins with the first vaccine, around six to eight weeks. In reality intestinal parasites arrive much earlier, often at birth. Roundworms, the most common worm in puppies and kittens, cross the placenta or pass through the mother's milk: a young animal can carry them while it still weighs a few hundred grams and has received nothing yet. Waiting for the vaccines to start deworming means handing the parasites weeks of free rein, precisely when the gut is smallest and most vulnerable.

There is a reason that concerns people too. Some of these worms are zoonotic, meaning they can infect humans, and small children are the most exposed because they touch everything and put their hands to their mouths. Deworming early and regularly protects the animal, but it also cuts down the eggs shed into the home environment. That is why international protocols place so much weight on the first months.

The worms that really affect puppies and kittens

Parasites do not all behave the same way, and knowing them helps you understand why the calendar looks the way it does. In the first months four groups matter most, with some differences between dogs and cats.

Roundworms (Toxocara): the most common in the young, passed from the mother, causing a pot belly, slow growth and sometimes visible worms in vomit or stool.
Hookworms: they latch onto the gut wall and feed on blood, so in very young animals they can cause serious anaemia.
Tapeworms: they show up later, usually linked to fleas, which is why fleas have to be controlled alongside the worms.
Coccidia and giardia: not worms but protozoa, they do not respond to ordinary wormers and need a specific treatment decided by the vet after a stool test.

The first six months, month by month

The schedule below gathers the intervals most widely used in European practice for healthy animals. They give you a first draft to take to the vet, not a replacement for the prescription: the final choice depends on the environment, on other animals in the home and on any symptoms.

Indicative deworming intervals in the first months. The product leaflet and your own vet remain the only binding reference.
Age	Dog	Cat	Note
2-3 weeks	First deworming	First deworming	Against roundworms passed from the mother
Up to 8 weeks	Every 2 weeks	Every 2 weeks	Repeated because worms mature in waves
2 to 6 months	Every month	Every month	The growth phase stays high risk
Nursing mother	Together with the litter	Together with the litter	Cuts the source of infection inside the home
After 6 months	By risk level	By risk level	Move to the adult rhythm, usually every 3 months

The trickiest gap is between two and six months: caught up in vaccines and socialisation, many owners forget the monthly wormer exactly when the risk stays high. Recording these dates alongside the vaccine dates, rather than on a separate note, is the simplest way to keep them.

Giving the wormer without waste or mistakes

The wrong dose is the most common error, and it almost always comes from weight. A puppy doubles in a few weeks: the dose worked out last month may be too little today. Here is the sequence that cuts both waste and underdosing.

Weigh the young animal just before treating
Use a kitchen scale for the lightest ones, holding them in a bowl or towel and subtracting the tare. A hundred gram error matters a lot when the animal weighs one kilogram.
Pick a formulation suited to the age
Liquid suspensions and pastes are easier to dose precisely in the very small, while tablets work once weight is steadier. Not every adult product is licensed below a certain age or weight.
Calculate the dose from real weight, not a guess
Follow the leaflet to the letter. If you are between two weight bands, ask the vet rather than rounding on your own, especially rounding down.
Give it according to the food instructions
Some wormers are given on a full stomach, others are not. For a wary young animal, hiding the tablet in a soft treat beats forcing it, as long as the full dose is actually swallowed.
Watch over the following hours
Seeing a few worms passed in the stool after treatment is normal. Repeated vomiting, marked lethargy or a complete refusal to eat are not, and they earn a call to the clinic.
Log the dose straight away
Note date, product, weight and time before the box goes back in the drawer. Memory does not survive a month, and without a record the calendar collapses by the second dose.

Keeping count and knowing when to call the vet

The first months' calendar almost always fails for the same reason: the dates live in one place, usually the owner's head. With vaccines, boosters and growth to track at the same time, a monthly dose slips away easily. A few habits prevent it.

Put every deworming in a digital reminder with a notification, not on a sheet you have to check yourself.
Record the weight at each dose: the curve also tells you whether growth is on track.
Keep the box or a photo of the leaflet with the history, so the next dose does not mean recalculating from scratch.
If several young animals share the home, treat them together and store the packs separately per animal.
Bring the full history to the first visit: it helps the vet decide the next plan.

Frequently asked questions

My kitten lives strictly indoors: does it still need deworming?: Yes. Even a kitten that will never go out can be born already infected, because roundworms pass from the mother. Eggs also come in on shoes, and fleas, which carry tapeworms, reach flats too. The plan in the first months is much like that of a puppy destined for the outdoors; later, the adult frequency will be lower but rarely zero. You settle it with the vet based on lifestyle.
I saw worms in the stool after treatment: did I do something wrong?: No, it is normal and in fact a sign the product worked. The wormer paralyses or kills the parasites, which are then passed in the stool over the following hours or days. What matters is repeating the treatment on schedule, because a single dose does not cover the eggs that will hatch afterwards. If you keep seeing worms weeks after each dose, though, mention it to the vet.
Can I use a wormer bought for an adult dog on the puppy?: Not without checking. Many adult products are not licensed below a certain weight or age, and an adult dose can be wrong for a small animal. Use a formulation indicated for the age, dosed on the puppy's real weight. If the only product at home is for adults, ask the vet before giving it rather than estimating the dose yourself.
Can deworming and the first vaccine happen on the same day?: Often yes, and it is common to arrive for the vaccine already dewormed. Many vets prefer the young animal to have been wormed a few days before the vaccine, because a gut loaded with parasites responds less well. Agree the sequence when you book, so you reach the clinic with the plan already clear.

What to do next

Start deworming around two weeks, repeat every two weeks until eight, then monthly until six months, always dosing on the current weight. Log each dose with date, product and weight in a reminder that comes looking for you, treat all the young animals in the home together, and ask for a stool test whenever diarrhoea or symptoms appear that a wormer does not explain.