Should People with Pets Take Deworming Medication?

Should people who own pets take anti-parasitic medication? As a general rule, no. Owning a dog or cat, or the pet receiving anti-parasitic treatment, is not in itself a reason for everyone in the household to take medication. We have specific guides on anti-parasitic treatment plans for dogs and cats.

Any suspected case of human parasitic infection should be assessed by a doctor or pharmacist. The medication, dosage and need for treatment differ between human and veterinary medicine.

Can some animal parasites affect people?

Yes. Some parasitic infections are zoonoses. Examples include toxocariasis, cutaneous larva migrans caused by certain hookworms, and some tapeworms.

However, transmission does not generally occur simply by touching the animal:

in toxocariasis, eggs from faeces can contaminate soil and hands and be ingested;
in cutaneous larva migrans, larvae present in soil or sand can penetrate the skin;
some tapeworms rely on the accidental ingestion of an infected flea.

The detail that changes everything: the environment, not the animal

Notice what these three examples have in common. In none of them does infection occur from petting the dog or from the cat sleeping in bed. The vehicle is almost always the contaminated environment: soil, sand, the ground in a park.

This explains a fact that often comes as a surprise — in the case of toxocariasis, the eggs passed in the faeces are not immediately infectious. They need weeks in the soil to mature. In other words, the danger does not lie in your pet’s fresh faeces; it lies in old faeces left on the ground, often from animals you don’t even know. That is why promptly picking up your pet’s faeces is a public health measure, and not just a matter of good manners.

Myths worth dispelling

“If my dog has been treated for worms, I should take the treatment too.” One thing does not follow from the other. The treatment plan for the pet is designed to protect the animal and reduce environmental contamination — it is not a treatment on behalf of the family.
“Sleeping with your pet transmits worms.” This is not the usual route of transmission for the parasitic infections mentioned here. What really matters is good hand and environmental hygiene.
“It’s best to take a tablet every now and then, just to be on the safe side.” Without a diagnosis, you don’t even know which parasite you have — and each one requires its own specific treatment.
“Can I use the dog’s worming treatment in a lower dose?” Never. The formulation, concentration and excipients are different, and some veterinary products are dangerous to humans.

Why not take a dewormer ‘as a preventative measure’?

There are different parasites, each with different treatments and contraindications. Taking a medicine without a diagnosis can cause adverse effects, be ineffective against the parasite in question, or delay the identification of another illness.

Never use veterinary products on a person. Even when the name of the substance seems similar, the formulation and concentration may be different.

How can you protect your family?

Keep your pet’s anti-parasite plan up to date with your vet.
Clear up faeces promptly and wash your hands.
Prevent children from accessing litter trays.
Cover outdoor litter trays when they are not in use.
Check your pet and its surroundings for fleas.
Wear footwear on potentially contaminated ground or sand.
Avoid feeding raw meat or offal without first assessing the risk.

Why are children the most at-risk group?

It is not because they are more vulnerable — it is because of the way they play. They spend more time in direct contact with the ground, soil and sand, and put their hands in their mouths much more frequently than adults do. It is this combination, rather than any particular vulnerability, that makes them the group most at risk from toxocariasis.

Hence, the most effective measures are simple and unassuming: washing hands after playing in the dirt and before eating, keeping outdoor sandpits covered when nobody is using them, and not allowing the sandpit to be used as a toilet by animals. This is more valuable than any pill taken blindly.

The vet has diagnosed a zoonotic parasite. What now?

Firstly, don’t panic: a diagnosis in the pet doesn’t mean the family is infected. It means there has been possible exposure and that it’s worth taking extra precautions. In practice:

See the animal’s treatment through to the end, even if it seems fine by the second day.
Step up cleaning in the days that follow — collect faeces daily, and wash the litter tray and your hands.
Tell your GP if anyone in the household has symptoms, or if there are young children, pregnant women or immunocompromised people in the household. State which parasite was identified: this information will guide the decision.
Do not self-medicate anyone — not even ‘just the children, as a precaution’.

When should you speak to a healthcare professional?

Seek advice if there are symptoms, significant exposure to faeces or contaminated soil, or a diagnosis of a zoonotic parasite in an animal. Tell the healthcare professional about the parasite identified, the vet’s findings, any travel history and the type of exposure.

Young children, pregnant women and immunocompromised people require special attention, but this does not mean automatic preventive treatment.

Sources

Informative content, revised in August 2026. This is not a substitute for medical or veterinary advice.