Fleas: learn more about them and what to do to eliminate them

Practically everyone who has a pet at home has gone through the pain of seeing their pet suffer from fleas and soon had to seek guidance and resort to flea remedies .

Fleas are external parasites that bite the animal several times a day, causing itching and can lead to allergies, wounds and shedding. 95% of them develop in the environment where the pet lives and not in his body.

This means that if your pet has a flea infestation, certainly the environment in which he usually has 95% more fleas than on his body.

The life cycle of the flea has 4 phases: egg, larva, pupa and adult. The phase that we can see is only adult. Due to this variation in the life cycle, the flea can adapt easily in any environment.

In addition, they reproduce very quickly. An adult female produces about 40 eggs a day. And they lay approximately 800 eggs during their lifetime.

When there are fleas in the pet, it is good to remember that they will also be on the floor, in the beds, on the sofa and in all the other places that the pet usually stays.

Therefore, if you find fleas or black specks (adult flea feces) on the animal’s skin and hair, seek veterinary guidance to start treatment as soon as possible with flea medicine .


Problems caused by fleas

Fleas do not only cause itchiness and discomfort in the pet. They can also transmit various diseases and cause injuries. Here are some other problems caused by flea infestation:

  • Constant itching and dermatological lesions;
  • Flea Bite Allergic Dermatitis (DAPP): This is due to the saliva that fleas inject into the animal’s skin through the bite, which can cause hypersensitivity, skin irritation and loss of hair (especially in the lower back), which can develop into injuries and infections;
  • Anemia: in cases of untreated flea infestation in the animal, the problem can worsen leading to anemia due to excessive blood loss;
  • Verminosis: the animal acquires the worm Dipylidium caninum, which is lodged in the flea, when it itches and ends up accidentally ingesting the infected fleas;
  • Infection with the bacterium Bartonella henselae: it can cause fever in the pet, inflammation in the eyes, gingivitis and cardiac and renal lesions, affecting the immune system;
  • Infection with the Rickettsia bacteria: the flea is a host of this bacterium, which can cause fever in the animal;
  • Bubonic plague: can be spread by contact with infected fleas. The disease can cause fever, chills, muscle pain and affect the animal’s lymphatic system, damaging the immune system.

How do flea remedies work?

As we have seen, flea infestation needs to be treated, as it can trigger several problems for the pet’s health, in addition to some of them also affecting the human being.

Therefore, the best ally at that time are flea remedies . According to experts, the drugs are the safest and most effective method of ending fleas, killing up to 99% of them in 4 hours of action of the medication.

Anti-fleas act in two ways: topical, when they act externally, and systemic, when the substance is absorbed by the animal’s organism and acts internally.

In topical form, the substance is spread over the animal’s skin and coat, affecting fleas when they move on the animal’s body.

In the systemic form, the medicine, whether applied to the animal’s skin or ingested, is absorbed by the body and reaches the bloodstream. When the flea feeds on the blood, it comes into contact with the medication and dies.

Types of fleas

Just as there are two ways of applying flea remedies, they are also available in several presentations, indicated by veterinarians according to the animal’s need and better ease at the time of application.

Check out the types of flea remedies available on the market below:


It is a well-known and widely used method to eliminate fleas by people who have difficulty giving pills to pets.

It can act in two ways: topical (external) or systemic (internal), depending on the manufacturer’s proposal.

The method of use is simple: the liquid from the pipette must be placed on the dog’s neck, so that it cannot lick. One must wait to bathe the animal again, so as not to remove the medication from the skin.


The pill is one of the most used and acts in a systemic way, that is, it kills fleas by sucking the dog’s blood with the medication.

Because it acts from the inside out, the action of the medication is not affected by the bath, unlike the pipette.

Currently, the market has chewable tablets and different flavors like meat. This makes it easier to give the medicine to your pet, as he can accept the pill naturally as if it were a snack.

Flea collar

They act by spreading the medicine contained in it on the pet’s skin and is absorbed by its organism, reaching fleas in a systemic way.

When choosing a collar, you must take into account the size of the animal so that it has the right amount of medication, so as not to intoxicate your pet.

In addition, it is important to observe product validity, as they must be changed according to the guidelines of each manufacturer to maintain their effectiveness.

Flea shampoo

Although they do not act as preventively as flea remedies, shampoos are also an efficient method of getting rid of parasites. Some products are able to kill fleas immediately while bathing.

Care must be taken when handling the product, so that it does not come into contact with the animal’s mucous membranes (mouth, tongue, muzzle) or is ingested.

It is important to remember that fleas can also be in the environment that the animal circulates, so it is necessary to clean beds, clothes and sofas to prevent your pet from being infested again.

Flea Talc

They can be applied to the pet’s body after bathing, in places with a higher concentration of fleas, such as the neck and belly, as well as in the environment where the pet is most, such as kennel, walk, house etc.

It acts externally, acting as a way of preventing and fighting fleas.

Remedy for flea and tick

For those who manage to administer the pills to pets, the market has products that are very effective in combating fleas and ticks.

Here are some options:


The Nexgard is a chewable tablet indicated for the treatment and prevention of infestations with fleas and ticks. It can be used in dogs from 8 weeks and weighing at least 2 kg.

Like most fleas, it should be administered 6 months apart, according to the manufacturer’s and veterinarians’ guidance. The medication is indicated according to the pet’s weight.

Information about Nexgard:

  • Start of action: 2-4 hours;
  • Maximum effectiveness (peak action): up to 6 hours;
  • Effect duration: up to 30 days;
  • Contraindications: puppies less than 8 weeks and 2kg;
  • Format: tablet (oral).


The Bravecto is a chewable tablet that protects against pet flea and tick infestation for up to 12 weeks.

It acts from the inside out and can be administered even to pregnant and nursing females. The medication is indicated according to the pet’s weight.

Information about Bravecto:

  • Start of action: 2 hours;
  • Maximum effectiveness (peak action): 8 hours fleas / 12 hours ticks;
  • Effect duration: 12 weeks (3 months);
  • Contraindications: puppies less than 8 weeks and 2kg;
  • Format: tablet (oral).

Frontline Plus (for dogs)

The Frontline Plus for dogs is a flea in pipette format, indicated for the control of flea, tick and lice infestations and protects the pet for up to 3 months. The medication is indicated according to the pet’s weight.

It also controls flea and tick reinfestations for up to 5 weeks, in addition to preventing the development of flea eggs, larvae and pupae for 6 weeks.

Check out Bravecto’s form of action:

  • Start of action: immediate action;
  • Maximum effectiveness (peak action): immediate;
  • Effect duration: 3 months for fleas and 1 month for ticks;
  • Contraindications: puppies less than 8 weeks;
  • Format: pipette (external use).

Remedy for fleas in cats

Like dogs, cats also suffer from fleas, although it is less common. The parasites can cause the same problems and diseases in both species.

So it is important to redouble your attention with your cat and keep an eye out for any sign of fleas. If this happens, the remedies are effective in combating them.

Here are some options:


The Comfortis is a chewable tablet, beef flavor, suitable for preventing and treating infestations of fleas for 30 days. It offers immediate relief to the pet.

It can be administered to adult cats and puppies, from 14 weeks of age and weighing at least 1.4 kg. The medication is indicated according to the pet’s weight.

Check out information about the Comfortis action:

  • Start of action: 30 minutes;
  • Maximum effectiveness (peak action): immediate;
  • Effect duration: 30 days;
  • Contraindications: puppies less than 14 weeks;
  • Format: tablet (oral).

Frontline Plus (for cats)

The Frontline Plus for cats acts directly against fleas, ticks and lice, and prevent the development of eggs, larvae and pupae of adult fleas.

It is also effective in the treatment of allergic dermatitis that can affect the pet due to flea bites. In the case of allergic animals, it is recommended that the application is made monthly.

The drug can be used in pregnant or lactating cats and is indicated according to the weight of the pet.

See Frontline Plus information:

  • Start of action: 48 hours;
  • Effect duration: Fleas 6 weeks and ticks 1 month;
  • Contraindications: puppies less than 8 weeks;
  • Format: pipette (external use).

Can a puppy take medicine for fleas?

It depends. The puppy cannot take any flea medicine, but can take specifics for his weight and age. It is important to pay attention to the manufacturer’s recommendations and follow the advice of a specialist.

Most brands have medications indicated for puppies or small dogs that act to eliminate fleas. Another option is flea collars, which are safer for puppies.

It is also important to remove fleas from the environment in which the pet circulates so that there are no new infestations.

Can fleas bite humans? What to do?

Yes, fleas can also bite humans . They are blood-sucking insects, that is, they feed on the blood of mammals.

In addition, they can transmit diseases to humans, as well as animals, such as allergic dermatitis, insects, endemic typhus , bubonic plague, bacterial infections, etc.

Flea bites in humans tend to occur more frequently in the legs and ankles and cause itchiness, which can lead to skin lesions.

The main sign of parasite infestation is small blood stains that remain on clothes and sheets.

To treat the lesions, it is recommended to thoroughly clean the area with water and antiseptic soap. Then, antiallergic ointments or pills can be used.

In cases of allergic people, the problem can worsen, causing fever , anemia and infection in the lesions. Therefore, these people should seek medical advice as soon as they notice a flea infestation.

Fleas in the environment: what to do?

If you have identified fleas in your pet, this indicates that there are certainly fleas in your home. This is because they are able to adapt to different places and like warm environments such as bed, sofa, carpet, wooden cracks, drawers, cupboards, etc.

It is important to combat flea infestation at home as they can also bite humans. In addition to causing itching and possible allergies, they can transmit diseases.

The first step is to pay attention to cleaning the house:

  • Wash your and your pet’s bedding;
  • Vacuum the entire house;
  • Clean sofas, curtains, rugs and mattresses;
  • Wipe all over the house and furniture.

An effective method is to make a preparation with lemon, vinegar and water and spray it on the house after cleaning. The mixture is capable of killing flea eggs and larvae, preventing the infestation from increasing.

Another option is to use specific insecticides for fleas after cleaning the environment. This causes any eggs that may be left to be eliminated.

It is worth remembering that it is useless to get rid of fleas in the environment if your pet still has fleas.

As they reproduce quickly, the ideal is to treat the pet with anti-flea remedies and to clean the house continuously, repeating the step by step to make sure that they have been completely eliminated.