Medicine for worms in the dog: how to care for the pet?

It is common for guardians to be concerned about the health of their pets, taking special care of hygiene, for example.

Despite this, there is often no way to control the contamination of dogs by worms, since the animals are in frequent contact with the ground and other places that may be contaminated.

To prevent this type of situation as much as possible, or even to treat cases in which the infection has already occurred, there are veterinary dewormers.

Keep reading and learn more about this medication and how to administer it to your pet!


What is worm medicine for dogs?

The medicine for worm in dogs, popularly known as vermifuge, is a medicine used to treat and prevent contamination by parasites in the pet.

It is usually applied after the first weeks of the pet’s birth and should be administered for life, usually twice a year.

There are different options and presentations of this type of medicine, which can be in tablet, liquid, paste, among others. There are also some homemade recipes that can help eliminate worms.

The dosage for application is made per kg of the animal. Thus, it is worth paying attention to the correct weight of the pet, to administer the medication in the correct way.

Among the options are:

For puppy

Puppies are generally more sensitive and need special attention. However, in most cases, puppies and adults can use the same type of dewormer, changing only the dosage.

However, there are some specials for puppy pets and small dogs. They are:

  • Vermivet Puppy for Dogs and Cats ;
  • Drontal Puppy .

Single dose

Single dose vermifuges are those that need to be administered only once, not needing a second application after a few days. That way, one dose is enough for the pet to be healthy.

Despite this, in some situations there may be the possibility that the professional will prescribe the medication for more days of treatment, as in the cases of Giárdia Canina, an infection caused by a type of worm.

Among the single-dose versions of vermifuges it is possible to find:

  • Canex Compound ;
  • Canex Plus 3 .


Tablets are one of the most well-known types of dewormer. There are great varieties of brands and active ingredients in this presentation, and among them are:

  • Vermifugo Agener União Helfine Plus Dogs ;
  • Milbemax C vermifuge .


Oral suspension, that is, liquid form, is one of the available presentations of the drug. It is usually administered in the mouth using a syringe, which usually accompanies the packaging.

One of the options in this version is:

  • Petzi Plus Suspension .

House made

The homemade versions are usually recipes made with ingredients easily found at home and are intended to assist in the treatment against worms.

It is worth mentioning that, although there are several versions of homemade recipes, consultation with a veterinary professional is essential and irreplaceable . Only a trained medical team can indicate the pet’s clinical condition and point out the best form of treatment.

Protocol: how often to do the deworming?

The deworming protocol may vary according to the health conditions of the biological parents and the environment in which the animal lives. In addition, puppies and adult dogs have a different frequency to receive the medication.

In general, puppies can receive the first dose of deworming at 2 weeks of age and alternate administrations until they are 1 year old. For adults, that is, after 1 year of life, usually the application is every 6 months.

Specifically, the deworming period for each age is:


Unlike what some people may think, worms are not only acquired in contact with the outside world, they can be passed from mother to baby during lactation or even during pregnancy.

Therefore, it is important that the pet receives the dewormer shortly after birth, so that there are no risks.

In general, the first application of the remedy is divided into 2 doses: one after 2 weeks of life and the other after 4 weeks.

After that, it is recommended that the puppy receives the medication once a month, until completing 6 months of life.

After 6 months, the administration is done every 3 months, until the pet becomes an adult, that is, complete 1 year.

2 weeks (15 days)1st dose
4 weeks (30 days)2nd dose
From 4 weeks (1 month) to 6 months1 monthly dose
From 6 months to 1 year1 dose every 3 months

When the animal completes 1 year of life, the protocol used becomes that of an adult.

It is worth mentioning that the frequency of doses may vary according to the general characteristics of each animal and, therefore, it is essential to follow the guidelines of the veterinarian.


After the pet reaches adulthood, the frequency of worming changes. In general, applications of the drug are made every 6 months , depending on the conditions in which the animal lives.

These applications are usually sufficient for the pet to be safe from worms. Despite this, it is important to follow the recommendations of the veterinary professional, who will indicate the best option for each animal.

How to dewormer the dog?

Wormers are usually administered orally, in the form of tablets or suspensions. There are also skin absorption options, where a paste is placed directly on the skin. In general, the application is similar to other drugs.

Despite this, as many pets do not like to take medicine, there are some tips that can help when administering.

It is worth remembering that, after application, it is very important to always check if the pet ingested all the medication, without spitting.

For each version, the best ways to manage are:


The liquid version (oral suspension) is applied with a needle-free syringe, which usually comes with the packaging.

For this type of medicine, it is important to always apply on the side of the mouth (between the teeth and the gums), little by little. This will make it easier to ingest and have less risk of the medicine leaking.

Just hold the pet’s face, open its mouth a little and apply from the side.


The vermifuge in tablets is one of the most used and found types on the market. There are more than a variety of this version, including chewable ones.

In that case, one option is to camouflage the tablet together with the animal’s feed. If the pet notices and does not want to ingest, it may be necessary for the guardian to make the application.

Thus, the owner just needs to hold the pet’s face, open its mouth and apply the medication directly on the bottom of the tongue. After that, massage your neck to help with swallowing.

Topical solution (paste)

Topical dewormer is the one applied directly to the pet’s skin, such as the neck or ear.

It is usually like a paste and, after administration, enters the pet’s bloodstream, acting similarly to the other versions.

The advantage of this type of presentation is not needing the pet to swallow the medication, which can often be a complicated job, since many dogs do not like to ingest the medicine.

How long does the worm medicine take effect on the dog?

In general, worms have a fast action, eliminating worms in a few days. However, it is worth mentioning that there is no exact time to achieve the expected effect.

The necessary doses and period of elimination of the organisms can vary according to the clinical picture of each pet.

It is also worth mentioning that it is often important to administer the dewormer in 2 doses, with an interval of 15 to 21 days between applications. This will allow the pet to be safer and prevented against other possible parasitic infections.

Why repeat the dewormer 15 or 21 days later?

Most vermifuges are instructed to perform the deworming in two doses, the second between 15 and 21 days after the first application.

This occurs because of the worms’ life cycle. These organisms reproduce differently, that is, not all at once.

If the dewormer is administered, it will probably eliminate all adult worms, but the larvae will not.

Thus, it is important to wait for these remaining larvae to become adults, a period that takes 15 to 21 days, so that they are eliminated with the second application of the medication.

What types of dog worms?

Worms are living organisms of different types that parasitize both animals and humans and infect them. In the case of pets, they usually affect the gastrointestinal system, causing digestive problems.

Despite this, there are worms that lodge in other organs such as the lung and even the heart, causing problems in their functioning.

Among the most common types of worms and worms to occur in dogs are:

Ancylostoma caninum

The Ancylostoma caninum is the causative parasite Hookworm a worms affecting the bowel.

Transmission is usually by contaminated food and water or penetration through the skin, in contact with places where the larvae are, such as lawns, for example.

There is also the possibility of transmission during pregnancy or breastfeeding, from mother to calf.

In general, the worm lodges in the small intestine and causes symptoms such as diarrhea , bleeding and anemia , since it feeds on blood and steals the nutrients that should be absorbed by the bug.

Giardia lamblia

The Giardia lamblia is a kind of protozoa that cause giardiasis , that when it affects dogs is known as canine Giardia.

It can be transmitted either through contact with other infected animals or with contaminated food or water.

This type of organism affects the intestine of the pet, causing symptoms such as diarrhea, vomiting, pain, lack of appetite, weakness, among others.

Toxocara canis

Toxocara canis is the parasite that causes Toxocariasis, a verminosis that affects the intestines of dogs.

Transmission is done by contact with contaminated feces or even by eating other animals that are infected with the worm. Contamination can also be done during pregnancy or breastfeeding, passed from mother to baby.

Among the symptoms of this type of disease are abdominal swelling and changes in the appearance of the coat.

Dirofilaria immitis

Dirofilaria immitis , also known as heartworm , is a parasite that causes heartworm, a disease that affects the heart of the pet.

It is transmitted through the bite of a mosquito, which deposits larvae in the dog’s subcutaneous tissue. After developing, the larvae move towards the lungs and the arteries of the heart, where they reproduce and release even more larvae into the bloodstream.

The main symptoms caused by the disease are cough , reduced appetite, difficulty breathing and tiredness .

How do you know if the dog has a worm?

In general, any change in the pet’s normal behavior can be an indication that something is not right with its health. Discomfort, pain and malaise can cause the dog to remain crestfallen, quiet and dejected.

Therefore, it is important to be attentive to the animal’s behavior and, if there is any sudden change, take it for a consultation with a professional.

Physical aspects are also important when it comes to identifying the presence of worms. Changes in the hair, belly and even the appearance of urine and feces are important when it comes to identifying a problem.

Among the main symptoms that can happen if the pet is contaminated by worms, are:

Swollen belly

Some worms can cause swelling in the animal’s abdomen, which causes a large increase in its volume, forming a ball in the pet’s belly.

If the pet has this sign, it is important to seek a veterinarian.

Change in coat and skin

Contrary to what some people think, worms do not only affect the inner part of the body, but can affect the hair and skin as well.

The opaque color and abnormal texture of the coat can be a great indication of the infection. If the puppy has dry and weak hair, it is important to be aware.

Itchy buttocks

If the dog exhibits a behavior of dragging its butt on the floor or trying to scratch the anal area with its teeth, it may be a sign of worms.

Anal itching is one of the possible symptoms resulting from a worms and the dog is looking for ways to relieve discomfort.

Vomiting and diarrhea

Some types of worms can affect the region of the digestive system and cause dysfunctions in its functioning. Thus, vomiting and diarrhea, with or without blood, can happen at some point.

It is worth mentioning that these symptoms are not necessarily indicative of worms, however, they are signs that something is not right with the pet’s health, it is important to consult a professional.

Change in the appearance of stool

Stool can be a good way to identify if something is wrong with the animal. If there is any change in its color or texture, such as the presence of mucus or blood, it is important to be aware.

It is also worth checking for the presence of worms in the stool. If the existence of larvae is found, the problem may be advanced and it is important to take the animal to the veterinarian as soon as possible.

Decreased appetite

If the puppy has always eaten well, but is eating less and showing a lack of interest in food, it may be a sign of worms.

The discomfort caused by the organisms can cause the loss of appetite, and can cause other symptoms such as the weight loss of the pet.

Weight loss

Dog weight loss is one of the signs of worms. This alteration can be caused either by the lack of feeding of the animal or as a reaction to some type of worm, when even the pet eating well, loses weight.

Thus, if there is a sudden and abnormal change in weight, it is important to take it to the veterinarian so that an assessment can be made and the cause of the problem identified.]

Taking care of the pet’s health is very important so that he / she can enjoy a good quality of life.

Among the actions that can be taken for this, performing frequent worming of the pet is a detail that can make all the difference.